I tried those KB Hyper pistons. You cant beat the price. I got around 15 races out of them before i burned a hole in one. Replaced it, Loaned the motor out ( bad move ) and it came back with 3 more bad pistons. So the hypers are laying under a bench somewhere and have been replaced with some SRP Forged pistons. The SRP pistons were only about $100 more then the Hypers. So for my money. FORGED!! they do take a beating.