Here we have a video from Renntech of their brand new performance exhaust for the Mercedes-Benz SLS AMG. It features a secondary catalytic bypass and x-pipe for an improved sound. Made by the American tuning firm, this is one of the first aftermarket performance exhaust systems we have seen for the new Mercedes SLS AMG. The new exhaust looks factory, however the growl you hear in the video below is definitely not stock. Hit the jump to see what your Mercedes could sound like if you let Renntech handle it.