I've used these systems on numerous cars, including a few GSR swapped civics. The system sounds the same as a greddy. Its got a resonator and uses an offset tip so the muffler doesn't hang down so far. One of my guys here at the shop is using the #1 headers and catback. The system sounds just as good as many others I've used and is full stainless. With a little tuning help from Scotty that car made 163whp with a stock GSR motor. Its not any more raspy as the greddy. Haven't heard the Apexi in awhile so I don't want to comment on how close it is to that one. Oh, fitment was fine too, no modifications necessary or problems with it.