Been using it for some time with no complaints. My car is driven daily and has 130k+ miles. Only problem is finding it in stock. Usually have to order it from the local O'reilly's. Bit more expensive than Mobile 1 but it seems to do the job.
I was reading about the castrol. It seems there are 2 similar, yet different 10W60s from Castrol. There is the TWS which is the BMW spec oil and then there is a Formula RS or Edge Sport. gets kind of confusing as some are the same but with different names.
I think the BMW TWS is an Ester based synthetic. I have used MOtul 300V (also ester based) in a different car. My oil analysis for that engine wasn't as good as when using Rotella Synthetic. those were both 5w40 oils though.
Formula RS was renamed to Castrol EDGE - this is what is recommended for our cars (at least the V8 model). Castrol EDGE Sport is a different formula which is supposedly not as good as EDGE (lower film strength, I believe). Searching on the internet, there seems to be some argument over whether TWS and EDGE are the same. Some say they are the same formula with different marketing names for North America and Europe, others claim that TWS has slightly higher film strength than EDGE.
Keep in mind, most of this is just what I found elsewhere on the internet, so I don't know how true it is. I just know that TWS is a lot easier to find than EDGE.
I also use Redline 10W-60. I have had no
problems to date. It's eliminated the dreaded
oil light (split second flicker) on dry starts. I
sometimes don't start my car for weeks and
oil light flicker was very concerning to say the
least and that problem is gone.
The only other comment I have is, it's the
thickest oil I've ever used. Pours out the
bottle like molasses at room temps.