Pros: Unbelievably quiet, even when it's being hit for data writes & reads. Fast performer.

Cons: First one arrived DOA. Newegg replaced it quickly though, but still an inconvenience when I was planning to use it for a full backup & upgrade. No cables or screws included - just the drive in an ASB with bubble wrap.

Overall Review: I use this in an external Vizo enclosure. It's so silent I hear the tiny fan on the enclosure rather than the drive. I'm buying more for internal use next!

Pros: Decent upgrade, but negated by failures Warranty replacement

Cons: Failures within months of use

Overall Review: I bought these from a brick & mortar store. One stick of the two started failing within a few months. PNY replaced them under warranty but one of the sticks was defective out of the box. The other failed within a 1-2 months of use. Thank goodness for the lifetime warranty, but I won't be buying PNY anymore.

Pros: Boosted system performance (temporarily)

Cons: Failed within a few months. Warranty requires original receipt. Warranty limited to original owner.

Overall Review: My laptop ran well for a little while. Then within a couple month I got BSOD reboots randomly. I didn't figure out it was the memory until after I started reinstalling Windows 7 and the installation kept failing. MemTest shows one of the sticks is riddled with errors. Given the warranty limitation and this product failure, I won't be buying any more PNY products - not worth any money savings.

Pros: Works with Windows Server 2008 R2. Super quiet. Solid construction. Super fast speed of eSata. Includes SATA to eSata adapter/bracket.

Cons: Heavy, bulky (thick), power adapter occupies three outlets side-by-side in a powerstrip

Overall Review: I bought two of these for alternating overnight backups. Didn't experience the drive sleep problems in other reviews. The fan on one of the units became a little noisy. Eventually, the enclosure became unstable. Backups started to fail. The server would recognize the drive at first but during disk access it would disappear and I had to power cycle the unit and rescan devices in Disk Management to have it recognized again. I'm trying to get warranty service,

Pros: Sleek, compact design. Fast transfer speed. Quiet for enclosure with fan. Both eSATA & USB 2.0 interfaces.

Cons: Minimal vibrational dampening for HDD inside - only the plastic frame. Support stand is marginally stable.

Overall Review: Bought this for backups and dropped in a WD Caviar 750GB drive. Works like a charm. The first HDD was DOA and I didn't notice because I mistook the cooling fan hum for the HDD spinning. The drive is super quiet and the fan is less noisy than some hard drives I've heard - definitely more quiet than a CD/DVD drive. Haven't used the dual-button backup features. I plug this into a HighPoint PCI Express SATA controller and benchmarked it at max 98MB/sec thru-put (avg 78MB/sec) versus avg 30MB/sec (28-32 min/max) on the USB 2.0 cable. Only issues I had with lockup were during boot-up but that's b/c the server to which I had it plugged wouldn't support more SATA drives at bootup.

Pros: Power under the hood. Stable, stable, stable. 2 USB ports and embedded Linux make it an invaluable tool for tech savy. Can squeeze hundreds of dollars of tech value out of this box.

Cons: Can't get all the expert features with out an external storage device (HDD or flash). Advanced features require Linux knowledge (or weeks of learning).

Overall Review: I bought 3 of these with plans to drop in 3rd party firmware (Oleg) and setup a VPN scenario for a few clients. A few months and several LOOOOOONG night later I learned enough linux to make it run just as needed. NOW, I have VPN tunnels and other features that would cost me at LEAST $600 in parts, config, and service using Cisco brands. I wouldn't have it any other way. Messiah's review is dead on.