I work for a large wireless company and have seen my installers put phones in every car out there from a Kia to a Hummer(couldn't hear it!) but every MB that comes thru ends up doing just what Benzmac says. Buy the handsfree made for the phone and have it installed using factory wiring for the antenna and have it wired for the radio muting. It works great! Good sound and reception plus it cost less! Look to spend around $400 for the equipment and installation unless you can do it yourself!