Well after talking with Zeb I went ahead and bought a set of the Stealths. I got them today and immediately put them on.
My impressions so far are:
They are a lot quieter than my monster ovals that I have had on for over 6000 miles.
They have a low sound to them similar to the monsters, but on the freeway they are a lot more enjoyable for me.
I can't tell any loss of performance vs. the monsters. I am running the PCV with auto tune module with a fuel moto base map.
The Monsters are probably a meaner or manlier sound, but I guess I am tired of them.
Overall they seem to be exactly what I was looking for, not a stock sound, but a nice deep sound and no drone when going 70 mph plus. That was my biggest reason I wanted something quieter. Up to 70 or so the monsters were ok, but when you are in the throttle they seem to bother me on longer 150 mile plus rides.
I haven't rode with them too much, but enought to know they are quieter in every aspect.
I am running a stock 110" with V and H true duals.