I've searched but haven't found this answered. I'm in search of an inexpensive downpipe to get me by for now. I have a Stillen style but I plan on going back with pre-cat elim/o2 tubes and an HKS cat back and Maximal high flow cat. The Stillen will have to go unless I cut and weld which I don't want. I'm hearing good things about the M2 system so I thought maybe I'll just get that and have an extra cat back on hand and can pick from the one with the sound I like. So my question is, if I want to save money and just get the downpipe, what's different between the M2 that comes with the full exhaust, and a CXRacing DP, or a OBX, or any of those eBays, or Ninja's for that matter? They all look the same. Are they all made by the same company?