Note that NorDac is a proprietary cloth manufactured for North. It is a laminate and should not be compared with high aspect or any cruising dacrons from Challenge, Bainbridge, or anyone else. As a laminate it has the potential to delaminate and mildew. Personally, I would not touch NorDac or NorLam. The jib in my avatar is NorDac. It delaminated and grew acres of mold shortly after the photo was taken in August. It's been replaced with a dacron sail from another loft.
With many of the Name lofts, you pay for the name, marketing, and franchise. The reality is that many if not most cruising dacron sails are made in Hong Kong at one or two huge facilities and "designed" by computer at the remote site. Unless the sail is made locally by a small loft, the local sailmaker does very little except measure for your sail; they don't actually make
the sail. High end racing sails area different beast; the sailmaker is much more involved.
Try Hong Kong Sailmakers (http://www.hksailmakers.com/)
If you want to see how a high end laminate is made, see the following. YouTube - How It's Made (Season 14 / Episode 4 / Part 1)