I asked a question in a different thread that essentially "M-stripes on a non-///M car" and the consensus was that it would be fine. Also, it was mentioned that you don't have to go with the colors that are standard, so mix it up a little.
As for the ///M badge. Absolutely NOT! That, and the engine, truly defines the car as a ///M car. Stripes, one thing, but badges... Eh... You're pushing your luck.