I have Borla's on my GTS and like them fine, even with hi-flo cats, 3" exhausts and fiberglass bulletts instead of the factory muffler at the rear. It is louder, but not too loud for me. You need to hear it installed on a car, however. I do get a little crackling and popping when letting off and coasting. It does have a drone at some speeds with the windows up, but this can be eliminated by shifting gears. It DO sound good at fullbore. I wouldn't change it. I heard a Corsa exhaust, and it did sound better than stock, but I doubt it has the power of the Borla system. I like plenty of h.p. My 2cents.