I would not use Koolance blocks, there are alot better quality ones out, that are cheaper too.
My first watercooling rig (that I'm posting from) included a koolance exos al system
Very costly and at the time only marginally better than my aftermarket heatsink and fan combo.
Ek 8800GTS full coverage block
I've heard in about two weeks, we'll start seeing full coverage blocks for the 8800GT.