for those contemplating or wanting a change in sound, consider the pipe from Mistral (along with the crossover). not only is it beautiful in design, the un-baffled exhaust makes the bike sound like it has a chevy small-block motor powering it. so fun, but you gotta like it loud.
2014 KTM 1290 Super Duke R
2012 Vespa 300 Super
past: Ducatis, Aprilias, Moto Guzzis, a Husky, and some BMWs as well.