I do not wish to stir up a debate re BMW's recommended oil change intervals.

The best way to find out whether you need an oil change is to have a sample analyzed.

The question is: How do you retrieve a sample from the E60?

In the good(?) old days, you could siphon a sample out of the dipstick pipe... Any E60 owners having their oil analysed? It seems to me that you could buy a lot of peace of mind if you spent the $$ to analyze the oil after, say 7,500 of your typical miles. If things at that point still looks "good as new" I would trust the BMW Service indicator from that point on.

Friendly reminder: I do not wish to stir up a debate re BMW's recommended oil change intervals.