I can't believe how spoiled some people from colorado are, if you're coming here from anywhere out of state, chances are you'll love copper. I used to go there for spring break all the time and it's real fun. I suppose I can't really say anything because I haven't been there yet this year, but their park is always solid, and the mountain is really fun as well. From what I've heard their park is better this year than past years, PLUS I've heard they have a park lift too.
Keystone is probably better, but I've always had lots of fun at Copper.