I had my first experience of BMW Emergency Service when my water pump seized, fortunately as I was just parking up at work (although the clouds of smoke swirling out from the grille were still pretty frightening)
The technician arrived in about an hour, diagnosed the fault in about 2 minutes and removed the old pump. He didn't have a direct replacement in the back of his 530d Touring and asked if I would like the car recovered or if he should come back with the part and save me the labour costs of fitting (which are included in the Emergency Service subscription if the Tech does it but not if the car goes to a dealer).
Obviously I chose the latter, he returned, fitted the new pump, allowed me to test drive the car with him alongside me (even though this was the first M5 Touring he had ever seen he didn't push to get a drive which was nice, I almost volunteered him the keys).
All for £115. Can't complain at that !