First off yours look great. If you are looking for rugged and flexible try Ultra High Molecular Weight (UHMW) Plastic. You can purchase it in sheets, and the Static Dissipative is natural black. I think it would be rigid enough to stand up to the forces of high speeds and flexible enough to take multiple hits from the curb. Think cutting board "type" plastic, UHMW in "nearly indestructible". This is what I plan to use when I get around to it.