There are 3 levels of certification for MB techs at dealers, certified is the LOWEST!
I have posted many times that there are good technicians at dealers & independants, finding them can be a problem.
THERE are bad apples in evert bushel, so you can get either at any place.
Integrity is a key factor in the auto-repair business as well as being competent.
I know several VERY good MB techs that have NEVER worked at a MB dealer!
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)