I am a proud owner of a 2008 550i and I want to put a new exhaust on it that sounds great. I am leaning more towards the RPI because of the reviews its gotten but I'm still not 100% sure. Any advice anybody has is greatly appreciated.

custom quad! :twoup:

or the RPI is a grate one with proven gain!

Remember guys, RPI only offers a "section 3" muffler for the 'i' class cars. Magnaflow only sells pieces.

Supersprint clearly wins in the performance category at +31HP with their full exhaust:

Attachment 133091

Best bang for the buck though is probably Magnaflow. :)

http://www.supersprint.com/en/prod-p...ing__06__.aspx

I'm going magnaflow. I'm not sure if it increases HP but I'm more than sure iit doesnt decrease it. That's good enough for me at tthis point wanting some growl from my exhaust

Magnaflow parts should be fine. https://5series.net/forums/topic/985...t-and-fiction/

RPI

we always recommend RPI for the guaranteed gains in power, and we run only RPI on our personal cars as well. if interested we are still having a limited time sale on all RPI exhausts currently as well.

How does the RPI sound in comparison to the magnaflow exhaust? I don't care too much about to power gains, more about the sound and which one produces the best sound.

Can you just say if Magnaflow is worth putting on or not? Way too much reading :twoup: