I think the tracker 800sx is the quietest on the market. We had one for about 3 years and loved it. Plenty of power and super quiet. Textron who makes it, makes many military vehicles and helicopters. They had roush of jack roush racing make all their engine and transmission mounts and exhaust and it is very wel done. We had a 6 seater and as our kids got older and started riding thier own sxs we went to a 4 seater honda talon. We love it but it is very loud compared to our tracker. We miss how quiet and smooth it was.