go to hondasocity.com and do a search under the name "muffler" then you will see some threads about 5 zigen. and like zidek_accord mentioned, there's a dude, called Deez, who has 2 custom 5 zigen on his 4 cyl and he video taped them on driving. from what i know, 5 zigen is neither loud nor deep. if u like louder exhaust, go with Tanabe Racing Medalian, or for deeper tone, Greddy SP or Evo