Apex ws, rs*r, greddy sp, tanabe hyper medallion, and comptech are some of the quietest after market exhausts around. You can also try custom piping with a magna flow resonator and your choice of oem muffler off another car to stay quiet and be sleeperish. The rsx-s, type r, cl/tl-s, 7G civic si mufflers are the more popular ones to grab to use for custom piping and the sleeper look. :thumbup: