I guess they are great only if you buy cars from them. I got an used BMW 2008 from private party(car is still under warranty), and the front bumper center screen (mesh) is broken. I took my car to Crevier, bought the parts at the parts department, and wanted the service department to install it for me. Service representative asked for more than $100 for it, would take the whole day to replace the screen. I decided to look up the DIY instruction here, and it took me 40 mins to replace the screen.
Just my experience with Crevier.