Mike said, "While the cost of the sails were about 220% the cost of Dacron I felt it was worth it...."
I''ve raced very competitively for almost 30 years using good quality (North) dacron sails, more-often-than-not beating boats with the high-priced sails (HPS). In club racing, the skill of the sailor means more than the quality of the sails. In more competitive racing, all the sailors are good, and you won''t be able to keep up with them if you don''t have good sails.
The HPS certainly outperform dacron. They give the greatest advantage in strong winds and in light air, because they are lighter in weight and less prone to stretch. You won''t see much difference in performance in "average" winds, when weight aloft and stretchiness is not much of an issue.
Most races are run in average winds. The question, as I see it, is whether it''s worth the expense, to you, to buy sails that perform significantly better in strong winds and light air.