I am looking at purchasing a c300. Nice car, dealer maintained. Was owned by original owner until sold to a relative. Has ~ 100,000 miles. In driving it it seemed to have more engine vibration that I thought it should have. I have a 2001 e430 so that is my frame of reference. Feels like a cheaper 4 cylinder car. I know this is a 6, but this engine has balance shafts I think. We picked it up at the dealer after service. Any thoughts? Mounts etc?