I fully see the benefits of building on glass, perfectly flat...however i do like pinning for the sake of keeping spars exact without any skew.... plus measurements on each rib is exactly spaced to achieve perfect surface area and wing loading....ive noticed lately alot of kits will give a round about surface area...however some wont handle the wing load according to the span...perfect example the Super sportster 90.- 120 I am building now...as calculations go the wing is about 3/8 too short..so I use the plans as a guide for layout but do not build exactly on them!! most any subtle imperfections on the wing can be taken out when its covered! by the way this is a scratch build all wood hand cut and shaped.....you can follow this thread in the scratch build section....thread name--Scratch build Super Sportster 120...using a Saito 150!