Picking between Whistler and Jackson is a nice problem to have. I still haven't visited J-Hole, but its quality is legendary. I spent nine days at Whistler in 2011 and the place blew my mind. Exploring it was a lot of fun and I spent most days on Blackcomb. Like any big mountain, you need to talk to the locals and learn about the dangers; lots of places to cliff out if you like to hike to steeper terrain. Its biggest issue, in my opinion, is not the crowds or price but the reliability of quality powder. Whistler can get great snow but they also suffer from a lot of heavy/wet snows like CA and WA... not that light powder you'll find in Utah or WY.