well got the full stainless on manifold, down pipe, de-cat, centre pipe, and a 4"burnt tip! and i cant even tell, yes it sounds mint but no gain i think if anything i think it feel's slower! it might be because my gear box is shagged???? my mate just got a gti and he was gaining on me nearlly got past untill i got in the way, but he would of if i didnt! would it be better with my normal air box on? just got a k&n on...........................