I hear a lot of stories about the solid style that hangs from chain, not solid attached to the back of the coach. Many have stopped large chunks of dead tire, and even lumber hit by the tires from reaching the toad. The mud flap was destroyed, but the front of the car, and the radiator were just fine.
I am for the large one on the back, but keep it 4-5" off the ground and you will not have issues with it throwing the loose road debris up.
Do either bungee it up, or remove it for the Alaska trip. Those roads can have some real deep pot holes.
__________________
|