KB is funnest on the street IMO. the instant torque is more usable and funner!
That's what I would pick.
Whippel doesn't make one for our motors
Vortec has the best support, and trouble free history.
Procharger makes good numbers, but if you have trouble their support sucks from history threads I've seen.
Powerdyne is more mild, but the silent drive on that belt is pretty cool too.
Novi 2000's are putting down great numbers too.