I was lucky enough not to buy a 1994 c280, because it turned out that most 1994-1996 c280's with inline 6 cylinder engines
have oil leak problems at the head gasket. I believe that replacing the head gasket only is not good enough. You need to send the head to some specialty shops to check/fix for straightness. Otherwise, a new head gasket would not do anything good for a curved head mating surface.