I stumbled across horse stall mats at a farm store and bought one to see how they'd work. I cut them into 8 in shares and some 16x8 rectangles.
They work great! I got them for a 5th wheel but now use them with my MH when I'm so out of levels that he jacks bring the wheels off the ground. I've used them under the jacks and under the wheels.
I've also used them to sandwich the Lego style pads to give extra height.
So far they have been indestructible.
Chasing 70 (degrees F) in a 2004 Travel Supreme MH, 2015 Jeep Wrangler, mountain bikes, hiking boots and swim shorts.