Pros: Edit: March 2016 - like other reviewers my pump started making noise after almost 2 years. Even on corsair's RMA website there's a drop down menu with the option of "pump is clicking or grinding", leading one to believe that this is a common enough problem. I RMA's this and the shipping cost close to $30 from Canada. I don't normally listen to bad reviews where people complain about DOAs or RMAs, but after this I'll be paying more attention. Do yourself a favor and spend an extra $30 on a better AIO cooler.

On the positive side, corsair's RMA process is painless and quick. And the 5 year warranty is while I'll buy another corsair AIO again

original review:
Keeps my G3258 (overclocked to 4.2) under 60c while playing a heavily modded skyrim for hours on end.

Great bang for your buck.

Fits nicely at the rear of my Antec 302

Cons: pump started to fail 2 years

Other Thoughts: worked great for almost 2 years until pump started making noise, maybe it had something to do with changing cases from a vertical tower to a horizontal HTPC

Pros: Didn't leak.

Cons: Pump failed after 2 years. Cooling performance was mediocre when it was working.

Pros: Not very quiet now.

Cons: I had some difficultly installing the cpu block to the motherboard, took a couple tries to get alignment right which only smear thermal paste more than I wished for. Instructions could have been written better.

UPDATE: I thought this was the quiet edition, not the fish bowl edition, after a month of use, now the loudest part of my setup. Its past the 30 days to return, plus I have already send off for the rebate.

Other Thoughts: There are only enough screws for one fan (which seem to be a #6-32 x 1-1/4" Black Pan Head Phillips Machine Screw and a #6 Black Machine Screw Flat Washer).

Pros: Small footprint
Supplied fan is fairly quiet
CHEAP
Does a decent job with better fans

Cons: Cooling capacity peaks at 110W TDP making it useless for AMD or Overclocking at all.
Supplied fan seems flimsy and has nearly no static pressure making the previous issue worse
Hoses are a little stiff, making it a trick to fit in some cases
Always makes a whooshing sound on startup, even in optimal positioning, needs more coolant

Other Thoughts: Frankly, it's not a bad cooler. The pump seems to flow quite well when listening to the air bubbles fly through the loop on boot. The fan supplied is a really bad design, allowing a lot of the air the blades are pushing to bypass and blow back in the opposite direction from the tips. With a replacement fan, say a Noctua, the cooler can handle most lightweight build quietly. But the low TDP cooling capacity limits it to stock clocked Intel and some lower TDP AMD builds, based on A series APUs or their Athlon brothers. NOT A PERFORMANCE COOLER IN ANY WAY.

Pros: - Keeps my CPU at a frosty 25-30 Degrees Celsius at idle, and Not too bad at load.
- Looks cool
- Nice Fan
- Fits my i5-4690k

Cons: - VERY HARD to install (See Other Thoughts)
- Stiff Tubes

Other Thoughts: So, I ordered the H50, and thought I had received the 50. Instead, I got an H55 with H50 instructions. It took me 2 HOURS to figure out how to properly install the thing, and I almost had to order more thermal paste because I smeared it everywhere. Although, I finally figured it out, and it works well now. Just wish I could of avoided the hassle, so I took off an egg.

Pros: This cooler does fit FM2+ socket, despite what everything says. I have it keeping my 860K nice and cool and have never gotten above 30c with a mild O.C. from 3.7 to 4.0.

Cons: Pain in the you know what instructions to follow.

Pros: Worked well for a year, cooled to 25-35C.

Cons: Past few weeks the pump has been cutting in and out. When it works, works amazing, but obviously as soon as it cuts out.. thermal shutdown. Only been a year or so, re pasting was not the issue as heat was transferred properly.

Other Thoughts: Maybe I got a faulty one, but I would not recommend this product in particular, however I have never had issues with corsair before this.

Pros: Relatively quiet. Get's loud under load, but there's no whining or air sounds.
Keeps my FX-8320 @4.5 GHz at around 30C idle and never goes above 60C

Cons: A little difficult to install if you haven't installed a water cooler before. I'd recommend looking up a tutorial rather than trying to decode the instructions in the box.

Other Thoughts: I'd recommend liquid cooling if your case has good air flow or if you plan on overclocking heavily.

Pros: 0 no pros nothing good about this product.

Cons: First off the back plate for this did not fit my 1155 MSI motherboard intel socket..... second off I had to take the pins out and install it manually.. Third off strange gurgling sound when this starts.... Fourth off the light does not come up on corsair logo as displayed and advertised... and last of all.. the product has no cooling capabilities.. my CPU was sitting at 65*C on 0% load... thats just disgusting for a watercooler.. Probably defective pump Also there was a condense of liquid like substance at the edge of the product.. kind of leading me to believe that it was pre-leaking. I made sure it was properly connected to the CPU and also added an aftermarket arctic silver thermal cream.

Other Thoughts: Do not purchase this unless you want to meet the worst quality of stuff ever.

Pros: I have this running for about a week. Im still in the middle of overclocking FX-6300. Im at 3.9 MHZ, Idle at 22C, Stress w/Prime 95 nothing over 37C. Thermal Margin is around 46F - 50F. THis is an outrageous cooler. Planning to go about 4.2 or 4.3 MHZ. Dont see why not.
Before I had stock cooler. Running at 3.6 MHZ, Idle @ 46C, Load @ 60C. ....you can see huge difference. Best bet is OC with Liquid, far better results.

Cons: not any right now.

Other Thoughts: For the price, this is a awesome CPU cooler. I wont be using air again.