Mac shorties, Bassani O/R X, and a Bassani aftercat system on mine. It's very loud and I get lots of people telling me it's the best sounding stang they've heard (of course most of these aren't car people), but I'm not quite sure what it sounds like from the outside while being driven so I can't say for myself. If I ever get around to it and can break away from my Chevy long enough I'd like to throw some longtubes on it since I don't have to do emissions anymore. I had a Mac aftercat before with the same x and headers and it sounded like absolute crap and droned much more than with the bassanis.