I watched the start of the Sela Ronda race in the Dolomites this year...9000 ft of rando climbing and descending in the night, 600 entries, $2000 prize, pretty cool event. The green monster was the boot of choice, but if they let them use xc skating boots it I'm sure they would all switch. The skiing was really easy. For tougher skiing, those boots might be a bit floppy.