About 5 years ago I did 10 days in Fernie over New Year and it was cool, but so so expensive (once there we heard they actual pride themselves on the most expensive lift pass in the US, at the time) - no joke, there's no weekly pass, just a day and season rate, so it was over £50/day EVERY day... This kept the resort v v quiet (even over xmas/new year holidays)... The topography of Fernie makes it a snow trap, to a degree, so it gets more snow than most on average, but D.P. is correct in the respect that easily accessible runs get tracked out quickly and the prime snow is a slog to get to (especially on a board) as it's a LOT of traversing.
I was recommended and stayed with
Canadian Powder Tours and the host (Susan) is one of the only locally qualified touring guides, and touring each morning was included with the accommodation price. There were only 2 groups of people in the chalet, so we all left in a group and got shown about on and off piste until about 10am when the other group went to a cafe for warmth/drinks and I got my own guide for the rest of the morning, resulting is some epic and memorable off piste. Yeah, it was crazy expensive, but I'd happily go back again and stay in the same place.
Saying all this... if you're after a "once in a lifetime" trip and are happy to spend enough to get to Canada, then the other obvious option is Japan... And, tbh, it's WAY more memorable... Last year I did Hakuba (with tours of snow monkeys, local shrines and a fire festival) and a few nights in Tokyo afterwards. Truly amazing... So much, I'm back to Japan in Jan, but this time Hokkaido to tour the area for 10 days and possibly snow-shoe up and ride in a volcano crater... only live once... Then more fun in Tokyo afterwards...