What I like about the Renegades, is the heel bulb part is separate from the part the hoof sits inside, so it allows the pastern to flex naturally. The heel bulb part holds the boot on, not the pastern strap, so there's nothing tugging on the horse's ankles with each step.
As for traction, the endurance riders use these things for 100 mile rides, so I'm assuming it's no worse than any other rubber boot. I would think they would be slippery on wet leaves or grass, but you can get them with studs already on them. (wish they made a version where you could add them as needed)
The only downside I can see with these it that small particles can get into the boot since they are a mostly open boot. It's kind of like walking on the beach in sneakers. Lots of emptying out to do later. Other than that, I really love these boots.
You just have to see your distance...you don't have to like it.