I ran a flowmaster 10 series (single chamber muffler) for a while and it had a nice deep tone to it, but it wasn't too much quieter than straight pipes (in my opinion), but there was a definite difference. I've only heard YouTube videos but I want to try the Dynomax Bullet race muffler, sounds fairly quiet yet deep. With that being said I'm running just front cats.... So any kind of muffler would be quiet to me
