Originally Posted by Plattus1000

Here's the tip of this debate iceberg http://www.m5board.com/vbulletin/e60...no-review.html loss of power after install. It's a "support upgrade" to support all the other stuff that you need to make it functional as designed. I had one, loved it but other than a cool sound and people touching it to see if it was really carbon fiber dinan stuff, it only helped because I had the other parts. (still digging)