I had an exhaust shop fab me an exhaust system for 250 which included a borla can. Smoking deal compared to what alot of these exhaust companies charge. I have the OBX header and while I like it and noticed a performance gain, there were some welding defects at the top of the header that OBX would not warranty. So while I have a couple of different items of theirs, if all your looking for is customer service from the company, RRM is the way to go. The differences between the header designs is such that the OBX 4-2-1 header is meant for mid to high RPM power while the RRM 4-1 is meant to be more designed for upper RPMS. I dont really think one is better than the other as both have their advantages and disadvantages. If you ask alot of people in this forum, they will say OBX is junk and RRM is the way to go. I however like both companies and have several items from each on my car. Just comes down to a preference for you. Oh BTW, yes my exhaust sounds good, however I went with 2.5in piping which is a no no for a naturally aspirated lancer. If you do decide to go the custom route, dont go bigger than 2.25in. I found out the hard way. Hope this helps a little.
Edit: So I was thinking that some people are going to want to know where I got my info on the header designs from. Mind you this link Im posting is for a honda motor, and a DOHC at that. But the results generally seem to be the same across the board. Header gains are greatly influenced by many factors including runner length and diameter which can shift the gain all throughout the powerband. Dont think too much for performance with our cars as you wont get much from either of the headers. I mainly picked the OBX as I thought it looked a little nicer, came with a downpipe, and was significantly cheaper. Just my $0.02.
http://www.hondatuningmagazine.com/t...est/index.html
