I checked into different options for my SB9SX exuast, intake, etc. I opted to go for the Buell Race kit, high flow air filter, race ECM, and a polished ceramic dual outlet racing muffler from buell. The bike runs well and sounds damn good. The normal race kit comes with a %!¤ty grey muffler, I paid a little more and put the polished ceramic muffler on and it looks really good, and has a finish like stainless steel would look. Real happy with the whole deal.