Bad service!!!

I recently wen t th dealership to service my car twice on funny sounds I receive when t engine is on. I also t it in the wheel balancing as the car vibrates between 110KM/H- 160KM/H. I would told my problems were fixed yet today the car, which doesn't even have have year, still gives me the same problem. Th evidence can been seen in a a tires and you don't have to be an expert to see the is a major problem. Is this the prestige image Mercedes is giving it's customers? If so I'm highly disappointed. I would rather buy another German brand car because they sometimes even call him from Germany to confirm if his satisfied with his service.