I have stayed at both locations a few times, including last July and we were there for new years, well in Duck Creek. The Hitch-N-Post Campground is ok, it but really a fisherman's place and we happen to like it ... Ruby's BLAH......
We will also stay at the KOA in Cedar City or at Fish Lake Resort and deal with the drive. It is a very nice drive too. Fish Lake is a very nice campground, over looks the lake, can handle the largest RV's and is relaxing. But it is two hours to Bryce... We enjoy Bryce Canyon, the hikes and the scenery. We like to ride our bikes or hike to the water falls.
But I doubt that I would ever camp at Ruby's again as, we have given it more then one chanse and it always fails..... Maybe it has changed but it was loud with motorcycles, quads, tour bus loads of rude people starting with the bus driver. They park and block everybody and the people in Ruby's could care less.
If you stay at the Cedar City KOA, Duck Creek or The Hitch-N-Post Campground you can hit Brian's Head, Duck Creek, short drive to Cedar Breaks and Zion.
JMHO