First of all if you want it to be loud, quit riding atv's. You give the rest of us a bad rep, that's why there are so many land/riding areas being closed down!! Most pipes are plenty loud enough. OK, enough preaching, I would stay away of the adjustables because they are notorious for leaking at the seems. They do have a non-adjustable that is pretty good. Toomey, Paul Turner, Pro-circuit, FMF, are all good pipes, what you choose is up to you and your riding style.