We've been using the Wiseco pistons for our standard rebuilds and they are holding 300+ hp no problems. If you don't like to wait to warm up the car in the AM before driving, then cosworth pistons are the route to go as they don't need nearly the warmup time of the other forged pistons out there.
I would not suggest replacing with OEM pistons, only because of their tendency for ringland failures...
11+ Years Maintaining, Modifying and Educating TriState Subaru Enthusiasts.
Call directly as We carry almost every manufacturer now, so before you buy parts call us.
Like us on Facebook! | E-mail: firstname.lastname@example.org | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) | T-1 Certified Amsoil Direct Jobber |AIM: AZP Installs
"Race Tested, Enthusiast Approved!"