A truly excellent ride.
I did that loop a couple of years back, we based out of Montrose because of the abundance of lodging and then just rode the bejeebers out of 550, etc. The only thing I would say to watch for is the time of year- you're going to go waaaaay up in altitude and then back down, and when you get up there, it can be friggin cold if it's not the high summer.
Have fun, it's a great ride.