I don't think I like the reliance on guide bushings to bore the holes. Too many variables there. I just used the Woodrave template and the Festool 20mm bit to do a 4'x3' top with 1/4" pegboard to get 4" on center holes. Using a straight edge and all the squares I have here it's as square as I need it to be. The downside possibly is the 4" on center locations vs the 96mm on center for a jig like this or the parf guide. I don't have any clamps at this point where that matters.