Performance is all relative, and "performance" with "accords" shouldn't be used in the same sentence. If you're modifying your accord for all-out performance, you're wasting your time.

I bought a Tanabe Super Racing Medallion dual cat-back setup made for an S2000 & had it customized to fit on my accord, but I didn't do it for performance purposes...more for show purposes because the dual exhausts look nicer than just having one. With the silencers in I think it sounds excellent, not "ricey" at all. Without the silencers, well...it's annoyingly loud.