And I've seen the pictures from Sweden, you were driving deep snow pretty much...
I took myself the car over the weekend for some snow driving, it was -5C and snowing heavily... (for here) 10 cm or so in a few hours... No big issues car handles well, and as you've said DSC seems to manage the RWD.
I did have a problem parking uphill, pretty steep hill, I had to later back out from the place and that gave me some wheel spins... nothing major, I was kind of expecting it ... so I parked with enough space to maneuver.
Had fun doing many power slides all over Lux... but I wouldn't put the car in M mode... Efficient and Comfort does the trick...
If I had to go Skiing up in the mountain, I think I would pass on bringing my M5... I would get the FWD Alfa for that instead.