I talked to my brother last night. He is a full time BMW mechanic and part time s14 and m20 builder. He said bmw now uses castrol synthetic 10w-60 in new bmws but recommends regular gtx 10w-40 or 20w-50 in older bmws. There are no 10w-60s in the chart, but I would definitely like to see some of the numbers on it.
Sidebar: My op light came on at idle again today. I bought a really strong magnetic retriever today and fished in the oil that I drained out of it last week. There was a very small amount of extremely fine iron particles in a gray film over the magnet. This could probably be considered normal. I would cut the filter up that came with that oil but unfortunately I threw it away. I ran the new magnet over each pleat in the filter I took out yesterday again and got a lot more. Half the particles were large and brown and looked like crystals of rust. The other half was gray finely ground unrusted iron. And there were also a few large chrome looking flakes.