I'd lean towards the Greddy exhaust myself.It's more of a N/A , street muffler.I't's good quality and it's not annoying loud like some of the cheaper exhausts.A friend of mine has the N1 on his JRSC Civic and he's happy with it except that he had to modify it at first because one of the bends comes too low to the ground and he kept bottoming out on it.It all depends on what look you are going for because the difference in power is minimal at best between the two.