Note: I am now 600 miles from the dealer that performed the work. I plan to have it fixed (again) by an official Mercedes dealer and then try to get the first shop to reimburse the second, or something.
From previous reading here about head gaskets, I inquired whether the head might need machining to ensure it was not warped. He said it would be a waste of time and money as long as the engine hadn't overheated after the gasket blew (which it had not).
I also vaguely recalled reading here about additional work that should be done during a head gasket replacement as a preventitive measure. So I asked him to let me know if there was anything else that should be done while they had it opened up.
He did not get back to me with any additional work recommendation, but when I came home... sure enough I found recommendations on this forum to have a complete valve job done at the same time, as well as replacing the head bolts, and resealing the timing cover. Grr...
