I know companies that use the 3/4 inch melamine, that is essentially a thin formica coating, to build cabinets, shelves, etc. The melamine is at home depot with a particle board core here in Tyler, Texas yet lowes has it with a MDF core. I know that both are well suited for garage shelving that is not in a wet zone. Take a look at a company called gorgeous garage. //sites.google.com/site/gorgeousgarageofeasttexas/Home, and you can see them using it on shelves that are rated for 1000lbs every 4 feet. It does have steel braces every 4 feet and an angle iron front piece, but that is a 2 foot deep shelf. If you used smaller braces spaced closer together, and a typical 12 inch shelf, I would think either product would work. The melamine is a nice, no paint needed surface, but plain wood would work too.