I've got a pair on my ol' thing, and I like them simply because they growl more than the stocks did. No real rasp, but the sound and all will depend greatly on the bike.
Of course, they're pretty much the only aftermarkets for mine, so the choice was easy. No real hp gains, if that's what you're looking for.
Dragging knee is for the track, and dragging tail is for the lot. --Kane Friesen
When you're in a car, you're watching a movie; when you're on a bike, you're in the movie. --Robert Pirsig
Identity theft is not Fun