Water is just too risky for me.
I used an H80 for awhile and the pump failed. Said I'd never use one of those bloody things again. But a few months ago I bought an H100. I don't know why. Yesterday the pump failed again. Bloody hel. If you are just a gamer and don't rely on your pc for anything else but gaming and want to push it too it's limits at all times, for what ever reason, I'd say take the chance and use a water cooler. But if you are truly reliant on your systems, don't. It ain't worth the risk. Luckily neither ever leaked so I wasn't going through the return hoopla with damaged video cards, mbs or anthing else, but there are just too many things that can go wrong and too many places it can leak and too much risk in high cost repairs and time waiting on refunds and returns, if you are lucky enough to get them. I have read lots of stuff both ways on all of that. So if you are just a hobbyist and can take the risk of a great deal of both time and money lost I say go for it, otherwise stick with air.