I just picked my car today with a new X-pipe installed by Fabspeed here in the East coast. Fabspeed specialized in tuning high end European sport cars like Porsche, Ferrari, and etc. they are looking into BMW now. Joe from Fabspeed worked on my M3 exhaust system in the past weeks, trying to find ways squeezing more power from the M3. We have looked at many options, and decided to replace the X-pipe at this stage. Fabspeed's X-pipe will eliminate the second catz and resonator. Everything else we kept it stock including the muffler, so no engine light issue. Our dyno'd showned 15-16hp gain at the wheel, which is more than what i expected. I have to say Fabspeed done a very nice job in designing and making great power increase, and keeping the noise at a manageable level. The car felt more responsive and quicker after 2-3k RPM. The exhaust tones are more aggressive, slightly louder, and it doesn't drone. The sound level pretty much unchanged at cruising, the sound different only comes alive when I push harder on the gas paddle.
Sorry, I don't have a good pic of the pipe coz i only got pics on the ground, but i am sure Fabspeed will post some pictures and video on their website in the coming weeks with pricing info. www.fabspeed.com