What clutch should I go with?
 

I'm looking at the Exedy Mach 500 w/ throw out bearing, and Exedy steel racing flywheel. Or the Spec Stage 2 with the same additional Spec parts. Is there any reason I should go with one over the other? Spec is slightly cheaper when everything is priced out.

I'm doing a clutch now because I'm about to have my entire exhaust, and driveshaft replaced, so it's already prepared for a clutch change. A supercharger is in my future FYI.