I hope I'm asking this in the correct forum. It's mainly DC2 related. I have the Apex N1 C/B on my R & the the thing fits perfect. I've seen so many other brands of systems that don't fit well @ all & have to be modified @ the local muffler shop. If I change to another kind such as Invidia, HKS, JIC or the like, can anyone tell me of some personal experience of good fitting systems? It would be most appreciated. Thanks!