Steve,
I have first hand knowledge of the Supertrapp, my neighbor (by the way, he's the one that just purchased the new S) has an 05 VRSCSE, and has had the Supertrapp for nearly a year. It looks great, sounds great (IMO), and makes power. One thing I will not do, is put something on a bike just to make noise, there has to be an enhancement in the bottom end, mid-range etc., before it interests me in any way. That being said, the Supertrapp being tunable is a definite plus.
If you'd like pictures of his bike or any other info about it, let me know. I was just looking for any other viable alternatives before making my decision. But the Supertrapp will probably be the one for me as well, it makes power, and has a nice tone without being obnoxious & setting off car alarms etc.
Barry