A couple guys on the Bonneville sites run a pair of the FM 40s series, or 1 single 80s if you just do one outlet. They seem to like it but I haven't heard any 3800 with exhaust work done that I actually like.
Nobody hears the car at idle so what good is it when it sounds like crap actually going down the road.

Ive heard good things of Magnaflow and had one on my 4-banger, but it just sounded like a nicely tuned 4-banger