I took my car there because it is an '86 and wasn't idling. I had them remove the carburetor so that I could take it to a specialist since they are incapable of fixing carburetors. The specialist told me there was nothing wrong with my carb, and that it was the stepper motor, and to have the mechanic check the computer of the car to see if it was telling the SM to drill too far into the carb. When I brought the carb back and told them what was needed they didn't listen to me. They put the carb back on and called me a couple days later saying it was fixed and charged me $250. Well, it wasn't fixed. They didn't actually do anything. And when I called to ask him if he even did what the specialist had asked and checked the computer he told me he didn't know how to do that; something he should have told me when I first asked him to. I said, "So you charged me $250 to take the carburetor off and put it back on and didn't actually do any work?" and he said yes. Wow.
If you have a simple problem I'm sure they're great but don't take your car here if you need an actual skilled mechanic.
Note: They moved some years ago. The new address is 1398 Folsom St. (downtown). It is the best place to get your Mercedes repaired.