I'll add that the Castrol Edge professional that BMW sold me is in a gold bottle and in small lettering towards the bottom, it does say TWS 10w-60.
Whether this is different from the gold bottles that say just TWS motorsport, I don't know. I called Castrol and they told me that the motorsport was a European product that was not sold in the U.S. Not sure how accurate that is.
I called another BMW dealership and at first they told me they carried TWS motorsport, but upon further investigation, they came back and said they now have Castrol Edge for use on the M cars.
Maybe I'm just nit picking, and they probably are the same. Just wanted to be sure before I top off my car.