What is your favorite performance muffler?

I grew up in an exhaust shop and preferred V-Force by Flo-Pro on my cars.They don't resonate like Flowmaster at all and are an aluminized stainless muffler.Nice crisp,smooth sound.They were a little loud when you really got into it,but sound great at idle and cruising speeds.Very little drone at highway speed.
http://www.flopro.com/vforce.html