I agree with the above post. has the most consistent good snow of any major co resort because it's cold and gets less sunbaked. However the good stuff can be hard to find. At winter park, the best terrain is definately not on the map. And the really steep terrain that is on the map hasn't opened yet and all snow in those places has been bombed away. Steamboat is a great big playground with tons of boulders and aspen groves. It's easy to find the good stuff. There is not much that is truly steep there though.
Vail has the most terrain and great cliff bands in the back bowls. Also incredibly easy to find good cliffs and things to jump off of. The back bowls get a lot of sun, so if you find cliffs with rocks sticking out farther than the snow on the take off, just sac up and jump over the rocks. A lot of fur coats and a lot of goobs hang out there, but it's still the shiz. Copper's got some long fun cruisers and their park is fun, but it's really got nothing on vail. Breck is flat and the good terrain is kind of out of the way due to the great lift system(thumbs down), but for park it's insane. It probably has local stashes too, i don't know. A-basin has some steep terrain and should be visited, but it's small and can get tracked out pretty fast. I've never been to beaver creek, a lot of mixed opinion's on that place. For snow conditions check out www.coloradoskicountryusa.com.
Keep in mind that some areas are full of bs though. Winter Park currently has better snow than any other major central colorado area including the aspen areas. Highlands' reported base is total crap by the way. I think you'll have fun anywhere you go, but i'd check out vail first if it's an option.