Well, I finally did it. I did Dr. Bob's VS800 exhaust mod. I only did stage 1 though because my long bit broke immediately when I tried to drill out the center baffle. The exhaust is noticeably louder, which isn't why I did it, but I think the bike has a little bit more power. My 60 to 100 runs felt pretty strong and I got the front end up a bit at a stop sign without really trying. My son thinks it sounds awesome but he's more of a loud pipes fan than I am. It's not horribly loud but it is deeper and more "muscular". I'll try to see if the MPG goes up.