As you said, you have the router table top sorted with that kitchen bench top material, I think this question is about the fence material. I know the original design uses PLY, but if I was making that design I'd also consider thick MDF, once it's sealed I've found that I have had no problems and it's still as true as the day I made it. I liked his incorporation of the table slide and am looking at making an attachment to do this on my table when needed.