i am either going with OEM or ACS.
the OEM sedan mirrors fold in, so that would lessen my chances of the mirrior getting clipped.
also, if i was careless (which i'm not!) in a tight situation the mirrors would fold or "break away" in the event they were struck.
when i say side-swiped, i don't mean run-off-the-road, i just mean the mirrors taking a shot.
the ACS mirrors are nice, but since they don't have a folding option, i'd be a little skeptical. they are pretty pricey and i don't have a garage.
i have not and will not consider any knock-offs or wannabe mercedes blinking mirrors, just not my style.