This system is still accurate after routing thousands of feet of strips. If you are going to do it in a similar way, add some wood glue into the screw holes. This board is just particle board with formica surface. Only a small hole is needed in the router table to get the router bit through without interference. The same goes for the slot in the fence.
Large holes increase the chances of the strip getting caught in the gap and cause other problems.
The life and accuracy of the fence is increased with a strip of formica epoxied to the poplar. Any hard, smooth and abrasion resistant material is fine. This becomes more of an issue when you mill many thousands of feet and more.