Originally Posted by MGRMLN

Yes! Do it!
I had Bavarian Soundwerks install my set since I'm in Atlanta and they did an amazing job. Jason and Micah over there are good people.

I got the MB Quart upgrade and the difference is day and night.
The stock speakers had muddy bass and virtually non-existant treble. Once you get them out and look at them, it's easy to see why. They look so bad! Cheap, paper cones and tiny magnets.

In short, the MB Quarts are great. Detailed but not overbearing treble. Tight, punchy and defined bass. My X5 does not have the sub but even without that, this upgrade is definitely worth it.