I just put an HMF on my 450 wolverine (I believe we share the same engine) I will let you know what its like once I get a ride in. You will need to buy the HMF or a similar jet kit with the pipe.
I have a HMF on my Suzuki king 700, but for it to run properly I used a power commander for tuning it. Basically change the mapping (fuel/timing settings)for the exhaust for better performance. It will have less back pressure with this type of exhaust better mid/top range performance. I don't use it any more, to loud and I don't run that fast any more, must be getting to old. Hope this helps to bad you didn't have the same type of machine I would have sold you mine.