Do you know where you are going... and when? CO is a big place. Holy Cross is where I would probably go if anywhere was ok. Telluride, Colorado is also insane.
Montana doesn't have mountains that are quite as high, but I prefer the scenery. Glacier National Park is on the top of my list...
The people are cool, but it was harder to find fancy food in Montana when I was there. Boseman had some good stuff.
Get some chlorophyll and put 5-10 drops in your water.