I used Creative V2 and I can say that it is almost 10% faster than a Powercolor V2, and it even worked in SLI with the Powercolor. I don't know about the Diamond, but Creative V2 is definitely a good choice.
Regards. Alpar

Wow, it worked in SLI with a Powercolor?. I've got the option of buying 2 12mb Powercolors as well, but I can't find any drivers for them on the internet. Would generic drivers work?

Ofcourse! Just use the drivers from 3dfxzone.it. (i personally like Fastvoodoo 3.5) They work with any V2, so do any other V2 drivers. You can use any V2 driver that you like. I repeat: if you are looking for performance, do not go for the Powercolor V2.

Hmm, interesting. I think I might just buy the Creative AND the Diamond, then SLI then and just use the FastVoodoo drivers. It's my understanding that the only reason reference designs from different manufacturers didn't work was because of driver differences, is this correct?

Not correct.  If you use two types of V2's, that doesn't mean that you use different drivers. Reference drivers only support mached SLI (meaning that the cards must be the same). Newer 3rd party drivers support missmatched SLI, so you can use different V2's in SLI. If you are looking for SLI, than you really should start with two identical cards.