Yes, if there was a problem that caused fires there would be a safety recall done so fast it would make your head swim.
MB has a team of engineers in the US that investigate accidents involving MB cars. A fire hazard would show up very quickly and be addressed very quickly. MB is not interested in a liable suit that involves loss of human life. Engine wear caused by FSS issues is a much different legal issue than fire.
Given todays economy and, sadly, the number of people willing to do such things as arsen(sp?) it's not surprising that you would see some expensive cars set afire.
Have a great day,