Big Gun was started by Mike Gunn who used to race dirt bikes competitley until he became paralyzed. He developes a pretty good exhaust for 4 strokes and they make a quality product. They have good service and offer a warranty against damage on the pipe. Check it out on there web-site. I have a Race series exhaust on my Raptor and it's been great. Pretty loud without the optional silencer. You can't go wrong with his suff as the fit and finish is good also.