Honestly, I'm not sure!
I really wanted to get this exhaust. I actually test drove a friends car and he had the M Perf Exhaust with a JB Tune and it was an AWESOME combination. I almost immediately went ahead with the purchase.
However my girl friend kinda woke me up! She did make a valid point. We were at BMW of Mississauga when a car drove by with the M Perf Exhaust and she immediately shook her head. The amount of sound you get from the M Perf Exhaust is not really worth the $1200 price tag. If I had to get an exhaust, I should get something that is a little lourder and has more burble while changing gears.
This all pointed me to the eisenmann exhaust. I researched and found a local dealer that would get me the Eisenmann Quad Tip exhaust for an excellent price. Acoording to some of the videos I watched, the sound is much better. However the sound clips were for a 328i!!!
Imagine a 335i!!!
So, I'm going to wait a bit and get the Eisenmann as it'll sound better and louder...