What's the diffference??

I'm trying to decide what to go with (shortblocks):
CHP 347 street fighter GTCHP 347 street fighter GT
CHP 331 street fighter

I'm planning on AFR 185's, and i really can't tell what the difference is between the shortblocks; As well as why the 347 is so much cheaper.

personally i like the 331 better, but for $300 and not much difference i'm willing to go to the 347.

stuff to go with short block: weiland stealth, AFR 185, Demon 625 (will i need more for the 347?)

Thanks for the help
-aj

Any one else have any idea? If it's just the $300 then i'm going to get the 347.