Last year we stayed at the KOA near Gould Co (NW of Denver). It's on the edge of Colorado State Forest State Park. We didn't stay at the State Park because we like full hookups, but we did go drive thru the campground. It was very nice, but I think the dump station wasn't working. There's electric at each site, water in a central location. The biggest problem with area was that the pine bark beetle has killed a bunch of the trees and they are logging them to prevent them from falling on campers. They had already done the KOA, we had heard that the State Park campground would be done as well.
We also stayed one night in Colorado River state park, Fruita section (just west of Grand Junction). It was also nice, full hookups, clean restrooms, etc. Note: the Island Acres section campground is located in a beautiful canyon just East of Grand Junction; unfortunately it shares the canyon with I70. Very convenient, but very noisy.
Further East, we've stayed at Rifle Falls State Park. It's very small; the main attraction is the falls. The park fills up with day users during the weekend. Oh yes, we also stayed at Ridgway State Park. We stayed in the Pa-Co-Chu-Puk section, again because it has full hookups. It's very out in the open, few trees, and it was hot there. But it was clean.
Overall our experience has been positive with Colorado state parks. I recommend that you plan ahead, make reservations, ask about specific parks to get specific answers. Enjoy your trip!
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