I am resurfacing my workbench with 25mm hardwood ply. I am inverting an up/down router and tablesaw into it (between tracks). I want to use thinner insert plates (for the zero clearence saw and so that both tools can raise and lower) What material for the inserts should I use? I want a max. of 10mm thick, prob. about 150 x 150mm and 100 x 150mm. Would MDF be smooth and strong enough, some sort of formica faced material ... alternative suggestions? Thank you in advance.