Hope you also make it over to Lake Louise while you are in Banff. It’a worth the drive over there.
As far as the LTX M/S goes, they’re not a dedicated snow tire, but probably give some of the best all terrain performance in the snow (when you compare them to other brands).
The bigger problem I have is, the downgrade to 20” inch rims instead of 18’s. Why not go to Costco (if you have one near you) and get a new set of Defenders on the 18” rims? I think they have a $100 bucks off right now for a set of 4.