My girlfriend and I took ours to a shop who diagnosed the same intermittent stalls as a faliure in the overvoltage protection relay. He changed the part and there is no difference. Part of the problem with their lousy misdiagnosis is that they were following a MB technical bulletin describing "stalls on acceleration". There were three fixes recommended, #1 to check the OVPR. So when the shop tech checked it, he found it failed his test, and he replaced it. But after that, there were no efforts to follow up on items #2 and #3 on the bulletin. They just said, OK its fixed, and gave us back the car, but it kept stalling. Make sure you check all avenues thoroughly.
At the next shop we are awaiting a diagnosis and I'll post when I hear.