That's a great kit.
I'm currently using the XSPC Rasa 750 RX240 Kit. Basically the same concept but with a weaker pump and an older CPU block.
It has no problem cooling my 2700k @ 4.9 and my 7970 @ 1.3.
The 5870 still providers alot of power. I was able to run basically any game with mostly high/ultra settings at 1920x1200.
If it weren't for my coworker offering to sell me his 7970 with a Swiftech waterblock for $300, I'd still have a 5870 and I'm pretty sure I'd still be happy with it.
I'd...