Go to Duke. UNC sucks
but seriously. It depends on what you are studying. If the program you are interested in is better at UNC, go there.
I was in the exact same situation as you a few years ago. I live in Atlanta, and my choices were georgia tech, boulder, and va tech. At this point, skiing was huge in my life.
I went to tech, and I am so happy I didnt go to boulder. Theres no possible way I could get the education I get now at boulder, especially in regard to architecture (my major). Had I gone to boulder, I would have focused on skiing, not school. To be honest, I dont get to do terrible amounts of skiing(around 20 days). But seriously, there are many other things besides skiing. My highschool self would be appalled by these statements, but being in college allows you to do many other things besides skiing.
Basically, my choice came down to this. Go to school for free, get a better education, and not ski so much for 4-5 years. Then take a year or two off (very easy in this economy) and ski. Ill have a better and more respected degree for free, and ski more later with better jobs.
You may really enjoy skiing a lot now, but skiing is really only a temporary thing, but your degree will stay with you. Im not saying having a degree from colorado, because its certainly not a bad school, but when you factor in cost and everything else, I think going with a better education is the right way to go.
sorry one last thing. I dont know what your finantial situation is. Other than 300 a month from my parents to pay rent, thats all I get. I pay everything else. My econ teacher who is like 45-50 came into class one day and told us he just finished paying off his student loans the day before since he went out of state. I was pretty set on going to colorado at this point, but i realized, its much better to get a free/close to free education, than it is to ski more and pay far greater to get a worse education. if taking a year off to get in state tuition works for you, then consider that.
sorry for the long post.