86K miles on my 530i. Not sure what it had for the first 30K miles of its life, but probably dealer-provided Castrol 5w30. After that, I ran either GC or PU 5w-40 in it. I just posted some pictures of it in the Photo subforum.
The C300 has about 56K miles on it, running M1 0w-40 typically. Sometimes if the service is done at the dealer, I think they use M1 5w-40 Formula M though.
IMO, engine lubrication issues are typically not what brings these cars down (presuming the right oil was used and changed on time). It's typically some other issue that makes the car not worth keeping... cooling system stuff, auto trans, electrical system, etc...