I have the 'Silent Rider' exhaust silencer, I really like it. It reduces engine power just a bit, but quiets the exhaust well. Between the silencer and running my carb air intake to the top of the roll bar with flexible dust collection hose and a foam pre-filter on end of intake hose (Intake noise reduced by at least 50%), My P-500 is now about half as loud as stock. Only things is, the silencer sticks out a couple inches rear, have nearly burned my shin or knee a few times standing near the rear to get something out of my cargo basket.