I've never ran one personally... but, I've ran with a guy at track near me who had one.. I can tell ya' that it's loud.. .. We both had Jato's, close to the same setup and both 2.5's, his was noticeably faster than mine.. I had a few more aluminum parts than he did but not enough to make that much of a difference (knuckles, C-hubs, rear hubs).... from what I've seen, looks like it's worth the $$ ....not sure about the other pipe.. also not sure which Resinator he had (I think there's 2 different ones right?)