Not a bad block at all, better than most in fact.
But at about the same cost the RBX and the White Water both offer more performance. For the very small cost differance I'd go with a White Water. Also I'd like it better if it didn't have a aluminum top, or offered it with a copper or brass alturnate it could be ordered with.
The new Fusion water block for cooling GPUs is a very good looking block. Good enough that I've ordered one. I like it's micro channel design and the brass top of the block. It should be here late this week.