Pros: Cooler was very easy to install and is working flawlessly. I know a lot of people have had issues with the fans and I was a little skeptical about it at first but I have not had any problems with it at all. I would recommend this to anyone looking for water cooling.

My cpu temps have not gone over 41 Degree Celsius under load but I don't overclock.

Cons: The only con I have is that I installed in my CoolerMaster 932 half and I had to make a couple of new holes for mounting but it was easy to do and you can't tell it unless you get up close. Other than that I love the H110I GT.

Other Thoughts: As I said I would absolutely buy this again and I would recommend it to anyone looking for cpu liquid cooling.

Pros: No unwanted noise, and doing its job.

Cons: None so far

Other Thoughts: Included in the build below, and works well being mounted to the front of the Thermaltake Core X71 case.

EVGA 220-P2-1200-X1 80 PLUS Platinum 1200 W
Thermaltake Core X71 Black ATX Gaming Full Tower
Corsair Hydro Series H110i GT High Performance CPU Cooler
Intel Core i7-6700K 8M Skylake Quad-Core 4.0 GHz LGA 1151 91W
GIGABYTE G1 Gaming GA-Z170X-Gaming 7 (rev. 1.0) LGA 1151 Intel Z170
CORSAIR Dominator Platinum 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000)
SAMSUNG 950 PRO M.2 512GB PCI-Express 3.0 x4 Internal Solid State Drive (SSD) MZ-V5P512BW
EVGA GeForce GTX 980 Ti 6GB HYBRID GAMING

Pros: Nice cool temps.
Creates a clutter free look in the CPU area of the board as opposed to air cooling.
Keeps temps well below anything that air cooling can offer.
Link software is okay and essential if your wanting to color configure your L.E.D. logo lighting on the pump head.
Pump is quiet.

Cons: None

Other Thoughts: Been using Corsair cases, closed loop liquid coolers, and DVD drives for as long as I've been custom building computers for myself and clients and I personally cannot complain ... much.
However, this cooler will not fit flush to the top of the Corsair 650D case. The reason? The bottom of the housing for the hot-swappable SATA3 dock (external) prevents the radiator tank from being flush with the top of the case. Therefore, it must be mounted at an angle of about 5% toward the front of the case. It doesn't take away from the aesthetics since the windowed side panel covers it, and it works every bit as good as it would if it were flush.

My Rig:

Corsair 650D Black case.
BitFenix Spectre Pro Blue LED case fans:
1 x 200mm intake (front), 2 x 140mm exhaust (top), 1 x Gelid 120mm Blue LED exhaust (back).
ASUS X99-A/USB 3.1 LGA 2011-v3 motherboard.
Intel Core i7-5930K Haswell-E 6-Core 3.5 GHz LGA 2011-v3 140W BX80648I75930K.
Corsair Hydro Series H110i GT High Performance Water / Liquid CPU Cooler.
2 x G.SKILL Ripjaws 4 Series 16GB (4 x 4GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000) Memory Kit Model F4-3000C15Q-16GRBB (32GB total).
MSI GTX 980Ti GAMING 6G GOLDEN EDITION
1TB SAMSUNG 840 EVO (MZ-7TE1T0BW) 2.5" 6G / SATA III TLC Internal SSD Drive (OS).
2 x Western Digital Black 3Tb 6G hard Drives (storage).
Ultra X4 1050 Watt Fully Modular Certified Silver Power Supply Unit.
ASUS PCE-AC68 Dual-band Wireless-AC1900 Adapter IEEE 802.11ac, IEEE 802.11a/b/g/n PCI Express.
Windows 7 Ultimate.
Vizio 42" 1080p 120Hz 3D LCD HDTV With Apps E3D420VX as monitor.

Pros: -just 8 screws and its ready to go
-works so well that it actually surprises me when my fans spin up

Cons: -None

Other Thoughts: -Make sure the fan size and CPU socket both match your case
-highly recommended and will buy again

Pros: - Cool
- Easy to install
- Software lets you customize fan speed

Cons: - Not as silent as I was hoping

Other Thoughts: I really like the CorsairLink Software. It let me set the default fan speed for very quiet day-to-day operation. With the fans set to 600RPM the loudest thing in my office is the Synology NAS across the room. My 5820k cpu is set to 4.2GHz and with the system doing nothing much and the fans set at 600RPM, the CPU temp is 28-30C in a room with ambient 24C. That said, I can still hear the fans and the pump. Also, despite the rated noise, the H110 is much quieter than my previous system which had a H70. This is probably because I set the fan speed manually with the software.

I agree with other comments on the confusing number of SKUs.

Longevity is TBD as I've only had this unit for 2 days, but the H70 has been going strong for 5 years.

Documentation is confusing in that the text says "we recommend mounting the fans as an air-intake to your PC case" while the picture shows air flow exiting the PC through the radiator. FWIW I mounted as shown in the picture rather than as an intake.

Pros: I got this up and running no problem. Mine's in the front mounted vertically in a NZXT H440. It's actually quieter than I thought. I can't hear the pump at all (on quiet mode at least). Fans are good too. Given the reviews about CorsairLink being problematic I was bracing for the worst. I downloaded the latest release and it worked the first time. I can see the all kinds of temps (including my Corsair HX750i), fan speeds, etc. I can control the LED, change fan speeds. It does exactly what it's supposed to. I'm very pleased. My CPU idle temps are ~25C ish.

Cons: None that I can think of.

Other Thoughts: CorsairLink is pretty decent; I like bringing it up and looking around. Fan and LED controls work perfectly.

Pros: Pretty good cooling.
Looks kinda cool.
Really quick and easy to get in touch with knowledgeable and friendly support.

Cons: EXTREMELY confusing naming conventions used for the multiple AIOs Corsair has at each "level".
Not THAT much cooler than Cooler Master Hyper T4 (~$25).
Pump and fans are not silent (I can see this REALLY bothering some people).
1 fan started rattling after 1 day of use.
Corsair Link software is unnecessary and a complete resource-hog (cpu/io usage).

Other Thoughts: First let me start out by saying I had a very difficult time choosing which Corsair cooler to go with. They have multiple AIOs at the same "level". I was able to learn that the ones with the tubes directly on top are made by Asetek and the ones with the tubes on the side are CoolIT. Supposedly, the CoolIT pumps have much better firmware (you can find forum posts by Corsair employees calling the Asetek hardware "silly" and very limited). Then there is the fact that the H110i is actually a newer version of the H110i GT (makes sense, right?), just as the H115i is the newer version of the H110i GTX. These newer versions are identical except for the fact that the block is a smidge smaller to allow for mounting on some tiny (mini itx?) boards. Everything else is exactly the same, but the H110i GT still has the older Corsair logo on the block (the rest I mentioned have the updated one).

Next, cooling. I had a Cooler Master Hyper T4 cooling an overclocked 6700k which kept it at 18c idle and the absolute max was about 79c under brutal stress testing. The H110i GT keeps it at 20/21c idle and the absolute max so far has been 74 (although it almost never goes past 68 even in p95/aida/realbench). That's not too much of a difference when considering the price and specs of these coolers. Also, I used Arctic Silver 5 on the T4 and GELID GC-Extreme (which is supposed to be far better) with the H110i GT...

As others below have stated, the cooler goes full-speed for a split second when starting the PC up. This isn't too troublesome, but can get a little annoying. The pump is also not silent. I usually have a window air conditioner blaring away less than 10 feet from my head but I still can't get myself to use "performance" mode because of the noise. Also, as others have said, the fans can rattle. I can't believe that after just 1 day I already have a fan that clacks away each time the fans ramp up... Unacceptable. Sure, I can swap them out for Noctuas, but that also adds about $60 to the price of this cooler....

All in all, I can't say I'm completely satisfied with this product. Right now I don't know what I'm going to do. Disassembling and returning a product like this is a huge deal, so I'll probably just shell out the $60 for better fans and hope for the best with the rest of the hardware.

Pros: this thing is freaking awesome, its my first time going with an all in one water cooler. sure its not expandable like the switech h220x2, but it pretty much is neck to neck with cooling.

using it to cool my i5 6600k skylake build overclock to 4.5Ghz with 1.24 vcore, idle temps in the high TEENS!! 16-19c reaching to 22c max and when benching to the limit full cpu throttle with prime95 and intel burn test the max temps i see are 62c

installing this cooler is easy with great instructions, the ability for the cpu block leds to change colors is nice

matter infact everything about this corsair h110 gt is nice

Cons: hmmmm someone say con, NONE AT ALL, well maybe the fans can be a tad bit noisier , not annoying loud, just a little slight hum that most people wont even be bother by it,

the fans only ramp up during heavy cpu usage when overclocking, when in normal use as in playing games having multiple firefox tabs with youtube running the fans are barely audible.

i been reading lots of reviews about this cooler saying the fans are like a jet engine and will blow your eardrum out , but thats probably when they are benchmarking stressing and with the fans maxed out, but in reality with a good air flow case and set up the pwn fan are controlled nicely through corsair link and you wont even be annoyed about the fans,

besides you don't even need to set the fans to max rpm, just lower your fan curve to around 70% or so, since 100% and 70% to me doesn't make any difference in cooling temps.

Other Thoughts: sure its not expandable or as good as an open loop coolers, but the corsair h110 gt is the best all in one cooler, with great led lighting and a very good software corsair link to monitor your temps.

i would highly recommend this cooler to all of my friends and to everyone else too, that 5 year warranty plus it will most likely not leak at all, the tubing with is very nice sleek sleeves are very well made and sealed.

Pros: I got this cooler for Christmas, and it has been running amazing. I have the 4790k, and was running on stock speeds on my air cooler around 45 degrees idle. With this cooler, 4.4 running idle hits around 22 degrees. Now, I run my 4790k at 4.9 GHz, 28-30 degrees idle, and a max of 78 under load for hours.

Cons: The fans face down and blow air up, and they rattle a bit on medium speeds. I contacted corsair for a replacement, they got back to me within a day, and they sent me brand new ones for free, didn't even have to return my origional ones, so I'm not docking an egg because of the great customer service

Other Thoughts: Maybe mounting the radiator vertically, not horizontally, would have stopped the clicking fans, but I have the Thermaltake Core X9 case, so there's no place to do that.

Pros: large radiator and fans
long tubes
cools very well
full control and monitoring
nice LED on pump

Cons: Corsair Link reports CPU temp 22 degrees lower than BIOS or other monitoring software. ( 10 C. / 32 C. Idle, 23 C. / 45 C. High load )

can get loud when under high load

Other Thoughts: When I was choosing the parts for my new system I wanted the best cooling I could afford. Several people recommended liquid systems. I went with this model because of it's size and the square full contact cooling surface. Obviously more surface means more cooling, and this one does it well. My FX-8350 @ 4.2G idles at 30 C and peaks under load at 38 C. Granted, I only have it mildly OC'd and I don't play extreme games, but it does what it should very well. (under default fan speeds)

The excellent cooling has one drawback, the fan noise. All the other fans in my system are fixed speed or set to run at the maximum inaudible speed. When the fans crank up to a high speed it gets just flat out loud. Fortunately the settings allow total control of the fans. With the fans set to Quiet Mode the noise is significantly lowered so it is only as loud as the case fans. The temps barely changed, idle at 34 C. and peak about 39 C..

The unit is sharp looking with it adjustable LED logo.

Hoses are long enough for almost any case but they may rest against the RAM if in a mid-size case.

Flaws in the software or the temp monitoring are only with CPU temp reported by the pump. It is 16 to 20 degrees off. I experienced the same issue with both the H100i and the H110i. This also requires the setting to be adjuusted if the LED is set on Temp mode, (the LED changes color as temps rise), if not adjusted to compensate the LED never changes. Annoying at best, not a deal breaker to me.

The fan cables and connectors are long. I would consider wrapping excess around the fans to tidy up as you install them. Installing the fans before putting the radiator in or before the mobo goes in is also wise depending on the size of the case and the placement of the mounting holes. I had to also remove the rear exhaust fan in my case to get this beast to go in. The instructions say to install the fans blowing down to improve system temps, having tried it both ways, down is the best way to go. Motherboard NB temps in my system are 5 - 8 degrees cooler even with frequencies at designed max.

Other System Specs:
CORSAIR Obsidiad 450D w\ Corsair AF LED fans
ASUS M5A990FX PRO R2.0
AMD FX-8350 4.0 GHz @ 4.2 GHz
G-Skill DDR3 2133 MHz 4 Gb X 4
XFX R9 290A EDFD (fans at 60 % fixed speed)
CORSAIR HX850i 850 Watt (fan at 50 % fixed speed)