Welcome to FlyerTalk Elliemae, that said, It is better to be as specific as possible in your posts so that the appropriate people will respond.

Convenience- If you are flying into Denver, Steamboat is a more convenient (closer) drive than Snowmass(Aspen). However, there are flights to both places (mostly from DEN).

Things to Do...What do you like to do? both have great skiing in winter, golf, hiking different festivals, etc.

Value- What kind of accomodation are you looking for? is it for a couple or a family etc? I would tend to say that Steamboat is probably the better value but it also depends on season and type of accomadation desired.