Got a chance to take a few pictures of the M Performance Exhaust before installing it on the car.
Basically, it's a straight perforated pipes with in the muffler chamber, like the ACM mod with perforated pipes. The entire exhaust is a lot lighter (Inconel material) and I can just pick it up by one hand, which I cannot do by the OEM exhaust. Also the exhaust tips are made of polished Titanium.
1. It is in-between OEM and ACM straight pipe with no noticeable droning at lower rpm (< 2000rpm).
2. Some small amount of droning at freeway cruise rpm (2000rpm - 3000rpm).
3. It is noticeably louder especially at higher rpm with some nice raspy metallic sound (> 3000rpm).