I ride at Bucks several times a year. As long as your course doesn't go through the woods, you won't hit rocky ground. The footing in the arenas is wonderful. I showed barefoot my first year but as we moved up in eventing, I decided to put front shoes on as I noticed a little bruising after an event.
At Bucks, just be careful in the parking area and around the hunt rings... this is where most of the rocks are. I stuck to the bridle paths instead of the roads to save Primo's feet.
As others said... nix the boots. They aren't designed for this kind of work.
If your horse says no, you either asked the wrong question or asked the question wrong
And God took a handful of southerly wind, blew His breath over it and created the horse