FWIW, I prefer a plastic cutting mat, but if I needed something large, I'd either use MDF or Masonite laminated to plywood or MDF. Melamine would also work. I've used plywood in the past, but eventually, you get cuts in the grain that start snagging the fiberglass. The fine grain and reasonably hard surface on Baltic birch is probably what makes it as durable as it apparently is.