I was between kooks and borla when looking at exhaust. I went with borla catback and have recently installed cat delete pipes. Sounds so mean and awesome. I say you can't go wrong with either. I've heard SW axlebacks are restrictive but a lot of people get offended when I say that so take it as you want. They have some great long tubes but I'm happy with what I have. I've also heard gt500 axle backs with o/r x and I was not impressed at all. My borla setup is a lot deeper and better sounding imho.