I was at our local "Christmas Tree Shoppes" which is a (small) step-up from a dollar store. There they had some type of an aluminum tray (with flimsy plastic lid) they referred to as a 'dessert tray.' It was lighter than steel. The reduction in weight is always welcome ... but the lighter weight may also mean they will be easier to keep on. They were also larger than 12" or 13" ... for those of us with larger rims (My Civic has 16" wheels).
Maybe these dessert trays are aluminum clad cardboard? They had a design molded into them that was hideous. That was the worst part, I think.
I think I'd rather have plastic ... then I can spray paint it black, silver or body color.
Still, I'm dubious of having anything permanently attached with magnets (that I'd have to source).
