Coming from Vancouver, I think that I'm pretty spoiled. I have Seymour, Cypress, and Grouse within 25 minutes from my house and Whistler/Blackcomb about an hour in a half away.
Since arriving in Japan, I have hit about 10 different resorts and the only one that has shown me some decent untracked powder, time and time again is Dynaland! No one seems to go into the powder that is just calling everyone to it. Anywhere there are