I love it!
It seems that that are playing around with different exhausts based on several vids that have been posted. Just an obvious thing being tinkered with among the hundreds of things that aren't so apparent.
Keep them coming, very cool to see.
330i ~ BMW Perf. Susp. ~ M3 Front susp ~ BMW Perf Exhaust ~ 3.38 lsd ~ SF71 Alf CSL reps ~ Continental Extreme DWs ~ Looking for e93 M3 fsb and e90 M3 rsb