I have a full debaffle, and it helps somewhat. I see a lot more people look over to see the cause of the noise when I'm approaching from their blind spot, but it's not infallible as they can still be quieter than even some of the hot rod car exhausts on the road.
From the pipes that I've heard installed on 9'ers like my own, the Bub's have been the best sound, as far as nice low tones. They are obnoxious loud though. Riding behind the guy who had 'em, I couldn't hear my debaffled stockers at all unless I tilted my head and focused on my own noise. Last I heard he was going to try and fab up some baffles for 'em to "calm them down", but I haven't spoken with him in nearly a year since.
The Cobra slashdowns had a decent sound too, although not quite as deep and rumbling as the Bub's. I *really* love the look of the Cobra swept pipes, and have heard good reviews on the sound, but haven't heard a set myself yet.
BACA Pretzel - Flyin' the highways in OK!
'08 Vulcan 1600 Nomad - "Grace"
Metallic Diablo Black/Candy Fire Red
Vance and Hines Duals
Kuryakyn Flame grips with Throttle Boss and Stiletto endcaps
Kuryakyn Longhorn offset highway pegs
Vista throttle lock
OEM light bar and luggage rack
B.A.C.A. Member, Oklahoma Chapter
Out to pasture - 2008 Vulcan 900 Custom: Redemption