I am sure that depending on the trailer, and the driver, there is some issues not good for the horse that is standing on all fours in the trailer bouncing down the road. Most of the new trailers have a better air ride shock system to eliminate the excessive bounce. Extra padded walls for the horses to lean. Some of us wrap the legs to prevent accidental bangs and bumps. ANd we drive as careful as we can to advoid jerks that pull out infront of us to avoid being behind us on the road, not realizing when we hit the brakes to avoid them we are possibly adding to any injuries that can occur to our precious cargo. Its nice to have someone ask. Now that you know please be sure to be kind when we are taking a little longer to pull into traffic and dont blow your horn it doesn't make us go any faster, it may upset the animal being hauled in the back. THANK YOU