what sound are you going for exactly. i have heard some sound ok at idle but they get all farty sounding in the rpms. guess it all depends what you thing Good sounding is.
seems like glass pack style mufflers are really bad about this...
my flowmasters always have sounded good just you can get rid of the killer bee sound up top...
and man reading through this thread some of you guys need to lighten up. some of the slant guys sound like they should be wearing panties. relax already.