Not really, I've run a stock dp with stock cat, stock dp with hi flow cat, and a delete pipe and really, the difference was not even noticable. I think it really depends, what hes going for. Daily driver / mediacore power numbers doesn't even really need it.Then again, I'm probably more worried I'll get stopped by a mobile smog check again...... Smog Nazi Cali.IMO, just run a high flow cat. I got the same response from that as the delete pipe on a Big16G.
'95 GSX - Big16G ~ Leaks, but atleast it runs.