It was great. I was only there for a like 72 hours, but we packed a lot of miles and elevation into that window.
I hope you can get there, too. It's easy to access -- right near Fort Collins -- and well worth the trip.
I bet autumn is amazing there. Mid-May was wonderful. The only word of caution, which I'm sure is obvious to people who spend a lot of time in alpine environments but not necessarily so to people from the East like me, is that the high peaks were still buried in feet of snow.