Don't listen to him, he obviously doesn't know anything about water cooling.
A kit will SUCK, trust me, you won't see a difference in temps between a fan system and a crap kit.
If you want a real water cooling system, I suggest you take a look at www.dangerden.com and piece a kit together yourself. If you don't know how to piece one together, it's not that hard, search google for the parts that make up a kit, then find them on dangerden.
You won't be dissapointed if you go that route, even though more expensive, it's worth it to do it right then wrong.