See this thread: http://www.xoutpost.com/bsws-mobile-e...oofer-kit.html

Short version: Yes, totally worth it, in my E53. I had them installed by a pro shop, and they said it was really easy. Instructions were great.

Go for it. I have zero regrets.

Dave

__________________
2003 4.4i (The X5 is WAAAY more fun than my Jeep used to be... )