I don’t get this, the Alps are not a million miles different to riding here, just longer descents in general – if you ride stuff here that makes you want a full face take a full face there, if you won’t ride the tough stuff take your XC lid. I’ve done both, I prefer the full face but I don’t remember riding any differently the times I took the XC lid. But I have done Les Arcs on bikes from 75mm elastomer sprung hardtails to 6 inch coil oil bikes and while I preferred the big bounce, it was still great fun on the clunker.
I never wear armour though, just too damn uncomfy. Personal choice eh!