Many of those prices for Cross cut dacron are apples to apples. The DP 280AP and 300SF are comparable cloths to ND78HA, other than the North reportedly has less resin.
My North sailmaker actually steered me away from Radian as he thinks for the size of the boat and my purposes it's a "better-buy" to go with the standard NorDac. Tri-radial cut may not have the advantages in a mainsail that it might in headsails.
I have no allegiance to a sailmaker, but I am leaning towards North for my needs in this instance.
