Metal wheel wells?

Went shopping for a new 5W yesterday at the Indianapolis RV Show. Really interested in the Cedar Creek and Silverback models but was disapointed that the wheel wells (area above the tires) was only a soft insulating/waterproof material. This is certain to be destroyed when the first tire shredding happens. Do any newer 5th wheels today have a hardened (metal) wheel well? Anybody out there ever bolt on their own metal plates?