Our fobs are very similar to that of a new Benz. Our fob is a little longer because of the extra row of buttons for the remote start. My fob fits into the ignition of my friends brand new Benz and will turn the switch but will not start it because of the chip. I will venture a guess that a new MB with remote start has the same size fob as ours. I have never had an issue and my fob stays in the pocket of my regular fit Levis or my suit pants.