Sun Valley is a riders mountain with 3,300 ft of vertical that you can ski every run. The big mountains like, Whistler, Jackson, Snowbird etc have lots of steeper runs that are broken up with a traverse along cat tracks to get to the next run. Sun Valley gets different weather systems to the Rockys but as most weather comes across deserts to get there, it can be as dry as the best. With no major mountains to block the weather systems, Sun Valley doesn't get as much snow as would like, but this is made up for by one of the best man made snow facilities anywhere in the world. Many a time have I driven from New Mexico to British Columbia looking for snow only to find top to bottom skiing in Sun Valley on man made snow with always perfectly groomed corduroy runs. If you are a wimp like me that doesn't enjoy skiing in temps below 20 degrees zero, enjoy the climate of one of Nth Americas finest. My tip for the serious snow rider is Dec / Jan Niseko Japan, Feb / March Sun Valley, Idaho.