I just got done going over these choices for my W140. The B66470207 speaks for itself. It is all chrome. That was not the look I was looking for on my car. The other two are more interesting for me anyway.

The B66470202 has a chrome ring and star with a painted silver background. The silver paint has metal flake in it just like a paint job. It is a little darker silver than the silver on one of my cars and if your car is painted silver (or have a painted wheel) I think this is a really nice choice. I was trying to match the wheel with the center ring and the B66470206 has the closest to the finish of the W140 polished aluminum wheel as the background to the chrome star and ring. It is the one that I decided to go with.