I've seriously looked at the Supertrapp option as a viable alternative to the PV2. I've got the PV2 on the Dragon and a new one in the box on hold for the IronMan, pending location of a suitable resonated stainless tip. I think a resonated tip would mellow out the PV2 without hurting the performance, but as you mentioned the Supertrapp allows tunability. There are several models that would work well, but you'd need to fab the exhaust from the stock box inlet back.