Big Sky has bigger terrain, but that doesn't necessarily mean it's better. Any advanced skier can ski 98% of the runs up there, but there's a ton of lines at Bridger I can never hope to do. Big Mountain just has really fun terrain. Nothing overly difficult (that I've found), but there's a ton of fun cliff bands back in the trees and on East Rim or Hellroaring. What I really don't like about Big Sky are their prices, the people, the rocks, and the poor snow quality.