Based on my experiences, make sure that any specifications, warranty or details you consider vital to the deal are in writing. MB are pretty canny about limiting information that could later be used, and you simply can't trust a salesman. I went thought a whole thing with MB & the Ombudsman about warranty on the EV parts, based on what we all believed was an official MB document, and something I used in making my purchasing decision. They insisted it was for internal use only. Ultimately, I did get it in writing, but it wasn't easy. Certainly soured me on the whole MB experience too.
I guess if you are leasing, it matters much less.