I concur. May also be slightly different width/shape to fit into wheel arch.
Given choice of MO and non-MO, especially on the front, go with the MO.
With the greatest of respect this is bo!!ocks. A 225/55/16 is a 225/55/16. With or without a MO label.
And I very much doubt that Michelin is going to make a different (better) tyre for MB - if it was better why would Michelin not offer it to others as well?
Marketing blah blah imho.