Pros: As usual, shipping time from newegg.com was expeditious and the hard drives (quantity of 2) arrived undamaged and very well packaged. Once I opened the shipping box, the inside revealed air cushion fillers and 2 WD-branded cardboard boxes. Each WD cardboard box contained a Hard Drive in a shock absorbing cradle. I was very happy with the shipping. - WD Red NAS hard drives are recommended by the manufacturer for use in home and small office NAS systems with 8 or less Hard Drives. - I have had 2 of these 4TB Hard Drives installed in my Seagate STDD4000100 NAS Pro 2-Bay Network Storage (Newegg items N82E16822178609 and 9SIA2W02VG7768). I removed 2 of my old hard drives from my NAS and I have replaced them with two new hard drives (each is 4 TBs). I then went through “diskless” setup of my Seagate NAS, which took about 20 minutes. The NAS needed to download new firmware and the hard drives were reformatted and I set them up in JBOD set up. The formatted capacity showing by my NAS was 7.9 TB. - After prolonged use and multiple large data transfers, the NAS reports Hard Drive temperatures of 41 and 42 degrees Celsius. I transferred large amount of data in multiple folders (about 40 gigabytes worth) back and forth between my rMBP and my NAS using wireless AC connection. Much to my surprise, large data transfers did not raise temperature of my hard drives. - NASware 3.0 is preinstalled. - 3-year limited warranty is pretty generous. - Interface speed: SATA 6 Gb/s. - Internal transfer rate/speed up to 150 MB/s. In real life I was clocking sustained transfer rates of about 108 to 117 MB/s over gigabit ethernet (desktop PC) and ac wireless (rMBP). - Drives seem quiet.

Cons: - When I tried to register these drives with WD for warranty purposes, I received “out warranty” status for both drives, even though they were manufactured in January of 2016. I opened “service case” with WD customer service and they were very quick to update warranty information for my drives. My new warranty expiration date is March of 2019. - I suggest you keep your receipts, check your serial numbers and make sure your warranty information is correctly recorded by the manufacturer.

Overall Review: - I was very pleased with the drives through out my testing. The installation process was painless, the drives are quiet and did not run hot in my NAS. The transfer rates are good. The drives are designed for prolonged use in NAS setup. The warranty is generous. WD brand is well known and price is competitive for the quality they offer. I have used these drives for about 3 weeks in my NAS. I have encountered no problems. Right now, I trust these drives with my personal data. - If you need spacious drives for your NAS, you can’t go wrong with the WD WD40EFRX drives.

Pros: - Fast data transfer rates - Very quiet - Low heat - Low power - Good price per GB - All data usable (IF GPT IS USED) - Very light

Cons: - Big drives (such as this one) do not play nicely with the old MBR style of using a drive.

Overall Review: Just to get it out of the way, you really need to use GPT with this disk. If you aren't sure what GPT is, give it a quick read on google. The cliffnotes version is: MBR is the old way of partitioning a drive. It only supports a few partitions and their size is limited. If you were to use MBR with this disk you could only use about 2.5tb of it. GPT is huge, and lets you do over 100 partitions and can be thousands of terabytes. Long story short, make sure you use GPT. I used this disk to replace a graphics and downloads drive on my home server. The old drive was a 1TB WD green from a few years ago. Since I figured I would give this drive a thorough run through, I copied all the data using a USB 2 external adapter sitting on the floor on top of the bag the drive came in. It copied a few hundred thousand files of varying sizes in a couple hours, mostly writing at about 31/MBs. I was surprised when it was running at how quiet the drive was and that it remained quite cool. After I pulled the old drive out of the server I compared the two, and this was actually lighter than the old 1TB green, I was surprised. In windows I ran a few crystal disk mark tests: The WD Red averaged 150 MB/s read and 130 MB/s write (Seq. 5 tests). The WD Green averaged 96 MB/s read and 88 MB/s write (Seq. 5 tests). Two Seagate 4TB drives (5900 RPM) in a Raid 1 averaged 143 MB/s read and 123 MB/s write (Seq. 5 tests). As the tests show, it outperformed the other drives, but the Seagates were definitely close and cost about 3/4 the price of the Red. I can't really speak for reliability since it has only been running a month, so my fingers are crossed for sure about that. My main problem with the huge storage drives available now is that it is pretty much mandatory to buy 2 in order to backup properly. You used to be able to get by backing up to tapes or discs, but it's just not feasible with something like a 4TB drive. Here's hoping that this drive has Western Digital reliability and treats me as well as the old Green drive did.

Pros: I tested one of these drives alone then tested two of them together in a RAID0 in my NAS. The single drive got: 164.5 MB/s aligned sequential read 0.573MB/s random 4K read 158.4 MB/s aligned sequential write 1.739 MB/s random 4K write That's fairly impressive considering the specs from WD say 164MB/s is the max write speed they got in testing. In a RAID0 array of 2 of these drives with a 128Kb stripe size, I got: 323 MB/s aligned sequential read 1.165 MB/s random 4K read 310.7 MB/s aligned sequential write 2.8 MB/s random 4K write That 1.8% loss on read and 1.23% write loss on theoretical maximum speed can definitely be attributed to my NAS's RAID controller. These drives' motors were incredibly quiet and could barely be heard spinning up when powered on. Setup was simple and it's clear that operate perfectly in a RAID environment with no mishandled commands or bad firmware error of any kind. I would definitely choose a drive from the Red series for any NAS I set up in the future. Also, historically, their failure rate is rumored to be around

Cons: The only con I could find is that the drives are audible from a close distance while doing a lot of scattered reading patterns. I've heard MUCH louder drives but I've also heard slightly quieter drives. There is one theoretical problem with these drives that I find very concerning. A huge company reported that out of their 776 3.0 TB WD Red drives with this exact model number, 8.8% of them failed in just half a year. That's ridiculously high in general but actually really low if you compare it to all 3.0TB drives from any manufacturer. In general, almost all 2 and 3TB drives are disastrously failure prone so this is actually one of the better one. I'd strongly recommend getting the 4TB version of this drive that does not have this allegedly high failure rate.

Overall Review: I reconfigured the RAID0 array to use a 16Kb stripe size and the speed dropped by about 2.5% across the board so definitely don't configure it that way. These drives do better with larger data pieces in RAID0 configuration.

Pros: Very smart and great for NAS machines. Huge size.

Cons: None that I am aware of

Overall Review: Western Digital is a leader in drive hardware. I am a fan.

Pros: Dual-plane balance control technology significantly improves the overall drive performance and reliability 35% MTBF improvement over standard desktop drives. 3 year warranty NASware 2.0 Low power draw High performance for its class Runs cool and quiet

Cons: None at this time for the drive. From what I can gather the premium support is free for the first call,subsequent calls may have fees. I didnt want to pose as an end user for the review and use my 1 call without need,rest assured if I ever have the need to call for support on the drive I will return and post an updated review.

Overall Review: I decided to setup an unRAID NAS server to test this device and it worked great from the secondary workstation but my desktop could only see the NAS not access it. I blame it on my machine not the NAS but that did keep me from transferring more than 200gb over the network to the server. The videos I did transfer to the NAS played back flawlessly,streaming videos simultaneously to the workstation was always smooth As nice as having a home NAS sounded though it was much easier to use this drive as a robust backup solution for the family PC that my spouse has been requesting. This drive clearly fills a niche and does so with finesse. power draw is low,performance is high. I couldnt find much out about NASware only what it was supposed to affect ,the video streaming enhancements were the most notable feature to me as a home NAS Admin storing video for streaming,other NASware features seem to be more relevant to business environments which is beyond the scope of this review.

Pros: Newegg sent me two of these drives to test, I used gnome-disks to test the latency and bandwidth and badblocks to test for errors. The tests were run on a Skylake iCore7 system running Fedora 23. I did overnight runs of badblocks on both drives as well as the built in SMART extended test. All tests passed with no errors and no errors reported in the SMART status. This says nothing about long term reliability but out of the box the drives are solid.

Cons: The performance of the drives is mediocre. I tested both drives at 1MByte, 10MByte and 100MByte transfers and for comparison I tested an HGST 3TB NAS drive in the same system. Western Digital WD30EFRX 1 MB sample size read 126.2 MB/s (1000 samples) (peak of 171) write 50.8 MB/s (1000 samples) (peak 56) latency 16.47 msec (1000 samples) 10 MB sample size read 126.2 MB/s (100 samples) write 109.1 MB/s (100 samples) latency 16.47 msec (1000 samples) 100 MB sample size 125.4 MB/s (100 samples) 122.0 MB/s (100 samples) 16.50 msec (1000 samples) HGST 10M 160.2 MB/s (100 samples) 97.1 MB/s (100 samples) 7.48 msec (1000 samples) 100M 161.5 MB/s (100 samples) 156.9 MB/s (100 samples) 6.72 msec (1000 samples) As you can see the read bandwidth of the WD drive is a 127MByte/second and the write bandwidth is at best 122MBytes/second. By comparison the HGST drive came in at 160MByte/sec read and as high as 156MByte/second write. The latency of the WD drive is terrible, 16.47 msec vs 7.48 msec for the HGST. For NAS applications I don't think these numbers are particularly important because the network connection to NAS system will be the limiting factor. In servers and desktops you should be using SSDs as your primary storage and hard drives for bulk storage so once again the performance doesn't really matter. In my Linux systems I'm using SSDs as caches with hard drives providing the backing storage, this gives me the speed of SSDs and the capacity of hard drives in a unified file system.

Overall Review: About Me: I'm a Newegg EggXpert, we aren't paid for these reviews but we do get free review units. I'm an engineer who has been designing computers since the 1970s. I specialize in networking and high performance computing.

Pros: I've built numerous NAS devices. My most recent was a 24TB system for a geology company. I chose WD Red drives (3TB in that case) for that build because I know what I am doing, and so does Western Digital. I used a Synology NAS and was extremely happy with it. + Key feature: These drives work *properly* in RAID arrays. (!)See note below. + Very low power usage and thus heat. The drive added about 6W in heavy use, 4W idle, including power supply overhead. This is even lower than some SSDs! + Faster than 3TB version. About 22% for random 4K writes. + Usually cheaper than the Seagate NAS 4TB (a competing drive). + Surprisingly fast transfer rate of 139MB/sec (including overhead). Note: DO NOT rate hard drives based on their transfer rate unless you mostly move large files to/from other drives! transfer rate has little to do with file server performance or even application load time performance! + Capacity per dollar is very high for a server drive. (!) Note from above: Technically any drive can be used in a RAID, but don't. Hard drives regularly grow or find bad sectors. Ordinary drives take so long recovering the sector that they are dropped from the array and must be manually restored which can take days -- time in which a second failure will destroy your array (at least for RAID5). WD Red drives feature TLER (which is less of a feature than a change to a timer in the firmware -- long ago even consumer-grade drives supported this) which prevents minor drive errors from leading to array failure. It used to be that only WD's RE-series of drives were appropriate for RAID, or expensive SCSI or SAS drives which cost much more per megabyte. WD Red drives don't cost much more than a standard WD Green drive, so there's little reason to take the risk on consumer-grade drives.

Cons: - If you are not build a RAID, there is *no reason* to get this or any WD Red drive. Get the Western Digital Green or one of its competitors. - This drive can sustain about 150 random IOPS. In other words, this drive is fairly slow for RANDOM I/O (many reads of small pieces of data from all locations on the drive) so is absolutely not a good idea for database servers, heavily-used file servers, email servers with many users, or heavy VM hosts. For those, you want at least 15K drives, but preferably enterprise SSDs such as Intel's DC3700 or a real file volume solution like one from NetApp. + I was unable to test performance in a real RAID with only one drive, but StorageReview.com clocked a 5-drive Synology array at 216 IOPS read, 531 write (4K). That's similar to competing drives but fairly awful in terms of server performance. It's comparable to just a single Seagate Cheetah 15K.7 drive, but the WD Red series is intended to be large, reliable, and cheap -- not blazing fast. (Note: If you need high IOPS and are on a budget, configure your drives as a series of RAID1 arrays. You will get near-linear scaling and will quickly outperform even expensive 15K SAS drive arrays. The downside is that you will have more than one file system, and will need to divide contents among them).

Overall Review: Credentials: I was a technical editor with StorageReview.com for many years. I was their first moderator, and I have a lot of exposure to hard drive performance metrics. I do NAS and storage consulting. I have a Computer Science degree and work for a major semiconductor company. Other notes: RAID5 is terrible for performance with any drives. It's good only if you need redundancy and lots of disk space. RAID0 does not increase desktop performance significantly. It's great for large file copies, though. If you want top desktop performance, ditch RAID and get an SSD. The difference is staggering. Don't bother making an SSD RAID array. If you are building something for your company, consider buying a commercial SAN. Yes, they are overpriced, but the added cost provides good CYA. Credentials: I was a technical editor with StorageReview.com for many years. I was their first moderator, and I have a lot of exposure to hard drive performance metrics. I do NAS and storage consulting. I have a Computer Science degree and work for a major semiconductor company. Brief notes for desktop users unfamiliar with RAID: RAID5 is terrible for performance with these or any drives. It's good only if you need redundancy (1 drive can die with no data loss) and lots of disk space. RAID0 does not increase desktop performance significantly. It's great for large file copies, though. I never suggest RAID0. If you want top desktop performance, ditch RAID and get an SSD. The difference is staggering. Don't bother making an SSD RAID array. If you are building something for your company, consider buying a commercial SAN. Yes, they are overpriced, but the added cost provides good CYA.

Pros: As I said in my previous review of this drive, it's extremely quiet and vibration-free. Quietest drive I've ever seen.

Cons: None.

Overall Review: I wrote in my previous review that I would buy a second one of these drives, and I did. I now have two of these in a Synology DS212j NAS, and it's dead quiet. So quiet, in fact, that I have to look at the LED indicators to see if the drives are spinning. Love them.