Glad to see you are going to swap-out that TT block. But since you won't change the pump\res and rad(s), don't expect to be blown away with performance. If i'd be you sswilson, i'd just wait, get more money back and once you have enough, i'd buy a whole new watercooling kit.
A MCRES reservoir (20$), a MCR320 (47$), an MCP655 (85$), a FuZion (67$) + some tubing, additives and finally soem hose clamps. Now you'd have something to talk about.
But yeah, to answer your question, yes. I still think that the Fu
Zion is the top notch quality CPU block available ATM. Now, if you want to get an Apogee GTX and bow it, it will then beat the Fu
Zion. But if you get an Apogee GTX and don't bow it, then the Fu
Zion is a better choice.
As for additives, well either Swiftech's HydrX or some G11 + Petra's PT_Nuke. Don't forget the distilled water
BTW: Last time i had a loop of G11 (10% G11 90% distilled water) + some PT_Nuke, algea still won the battle... But lots of ppls says that it's a good combo to prevent algea. And a lot have not got any algea in their build with that combo. I did, go figure why!