I already owned a bunch of Yakima stuff, so I bought the roof mounts for my mercedes. They work just like the BMW. I do use a front wind deflector. I love the Yakima High Roller bike rack. Just toss the bike up there, wheels and all. Takes just seconds. The rack stays on year round. In the winter it gets a ski rack. For road trips and camping, it gets a cargo box. Very handy, and personally, I don't think a car looks complete without a roof rack. It took me about 5 years to forget the bike was up there and pull into the garage, trashing my car and bike, so beware!