For what it is worth, Rick Cecco, factory rider for can-am, runs an HMF pipe on his race quad as well as his practice quad. According to him, the only differenee in what he runs between the two is sound. He likes to be loud on the track so folks know he's coming and to move over.
The muzzy stuff from what I hear is very nice as is Leo but we've yet to test either on a can-am product. Both companies make a very nice setup for the Renegade as well as the Outlander but we don't have any way at this point to know what kind of power they make.
I was pondering an HMF for the Project-X quad and doing a fuel controller but am just on the fence if I want to go loud or not.
If any of them wanted to do something for both of our Can-Ams, we would probably do something for you guys for a review.