Ok, here's a really super read about engine oil, with specifics for B58s amongst others:
BMW engine oil info and recommendations from the leading independent BMW tuner in the USA.
www.bimmerworld.com
My take is this. 0w-20 is too 'thin', and yes it's to meet CAFE and not for longevity. No, our B58s (or B57s) aren't modified with bearing clearances and all that stuff to require 0w-20 and going higher weight will harm the engine. And I think a 0w-30 or 5w30, for daily driving, with Euro specs, LL-04 approval, will be best for longevity.
The B58 from what I've researched is bulletproof -- the stuff around the engine, not so much, and that's where we have to inspect and focus on.
LL-04 is where to be, but a more modern and well-additive-ed LL-04 oil. I'm doing oil analysis at each change, and it's enlightening. Latest was Red Line, and boy, yes they do have ZDDP in there. Have a few more brands and weights to test, but at the moment, my bet is on Red Line Euro series 5w-30 for best longevity, esp. for the turbo. But I will test Castrol's Euro first, maybe Mobile 1 next, and with the oil analysis I should be able to see ZDDP levels -- Castrol doesn't seem to publish HTHS values, but LL-04 mandates an HTHS value of 3.5 or higher so it has to be at least 3.5. I always make sure I'm using API SP and if available SQ, for the timing change -- not that SP isn't ok, but SQ requires the tests to confirm timing chain effects.
Can't get non-ethanol gas in VA where I live, but in FL when I'm down there, yes sir, can get that.
I only use Top Tier gas, always 91 octane or above, and I cycle through Shell, Chevron, Exxon, Texaco (when I find it), and others.
/s.