Well, I put a Flowmaster Series 40 muffler on my Alero, and it sounds pretty good! Just the right sound level. Enough to rumble a bit at idle, but no drone or resonance at higher speeds. Can't beat this deal! Got it installed and a 2.5" rolled round chrome tip for exactly: $0.00
That's right, free. Those are the perks of working at a shop.

RD