My old workbench top (2x material laid on the flat over 2x4 crossmembers) has developed some really bad cracks and warps. I've never been thrilled with it - it's a little too wide, the crossmembers always got in the way when trying to add vises. So trying to flatten it and fill in the crack isn't really something I'm interested in doing.
Two recent projects have left me with some decent 3/4" sanded radiata pine plywood (haven't seen any voids when working it) and 3/4" mdf. I have enough material that I could make a new benchtop of either 3 layers of mdf or 3 layers of plywood. The bench will adequately support the top that I'm not worried about sag.
I'd like any recommendations and which way to proceed.
I work full time, have two kids, am in school, and have a list of projects as long as my arm, so I will politely ignore any recommendations to build a benchtop of laminated 2x4s.