Well that is really rider preferance. It is all in what you want. I have a utility series. I love the power gains that I got, but, I don't like how loud it sounds. I would much rather something quiter with a little more deeper sound. I ride just mud and water. Speed is not something I am after. I want torque and am willing to deal with the noise to get it. I may find another pipe one day, When I get my lift done I will probably get a different pipe custom installed on my bike, then get it dyno'd to best performance. What kind of riding you do? What are you looking to get out of yours?jrich wats the best pipe for a 500 foreman