Just browsing on eBay and came across this little gem. It's a custom subwoofer box for the X5. I can see the company has sold 10 of the enclosures so surely somebody on here has some experience with it?

How easy was installation? Was the fitment ok? Difference in sound from stock?

BMW X5 E53 1999 2006 Custom FIT MDF 10" SUB BOX Subwoofer Enclosure Bass | eBay

I might give one a try next week!

__________________
2007 E70 X5 3.0D Black/Beige - SOLD
2012 E70 X5 40D Silver/Black