My SO and I rode there a year or so ago - I loved it! The owners were both incredibly nice people. Gene (I think that was his name) really knows the trails and is a great resource when it comes to recommending which ones to take based on how long you want to ride, and what kind of riding you like. He'll mark up a map for you to show you where to go, and the trails were pretty well-marked.
The camp was well-kept with nice stalls for the horses at night and nice, flat sites for a wide variety of trailers and rigs. I can't remember for certain if they allow you to set up high tie lines or not.
You can access the trails from a few trailheads at the camp, so it's nice not having to backtrack when going in and out of camp. Everything from riding along the top of a ridge to riding down alongside a stream - one trail was pretty washed out but most of them were nice.
Noteworthy, though, is that some of the trails are shared with ATVs and dirtbikes. We ran into a couple of groups of them - one understood the concept of trail etiquette, the others just flew on by. And some people complain that horses
tear up trails.
Would I go back to Red Hill? You bet. We were only there for a weekend so we didn't get to do much riding, but I would absolutely love to go back and see more of it.