If anything, I'd drive my MB in the winter, and find something else for the summer!! These cars are GREAT for winter use.
The RWD and near 50/50 blalnce make them agile, and some top-notch snow tires takes car of any potential traction problems.
As to wear and tear, make sure that you don't cold start your engine and then abuse it. And don't shut it off cold.
MB's have about the best rustproofing around. We drive through terrible amounts of salt, and MB's don't seem to care. Wash it weekly, and I DON'T heat my garage. Heated garages might be comfy, but your car is always wet.
The only complaint I have is the large number of rock chips. We used to sand the roads, but in the last 10 years, they seem to be using gravel. This means a real beating for your hood, leading edge of the roof, and rocker panels. I have 3M tape on the hood and front spoiler, and it makes a huge difference. Expect smashed headlamps too.
If I had to park indoors (as I used to at work) I just stepped up my wand-wash schedule to twice a week, and that seemed to work just fine.
Wash the wheel-wells, and the undercarriage. Get all the nooks and crannies around the suspension points.
Enjoy winter driving in your MB! Remember, Germany gets winter too...
