it really depends on what cpu you have and what games you are going to run.
if your cpu is very slow(pentium3 etc), and you aren't going to mess with any dx9 games, then 30.82 is the fastest.
if your cpu is very fast(k8 for example), 66.93 may be faster.
if you want to go for some late dx9 games that it would struggle to run anyway(NFS most wanted for example), go with 93.71, its most optimized for them.
last but not least, the 4x.xx~5x.xx series do yield highest score in some dx8 and early dx9 tests(3dmark01 and 03 for example), but them are also the most buggy and unstable for me, i guess they are just busy cheating with their pathetic geforce5s in those days, so i would avoid them at any cost. they won't work well with late dx9 games either.