poking around on Doyle's fabric selection page, it would appear the type III (woven, film, scrim, film, woven) might be the best overall in terms of stretch and durability?

I'm sure it's heavier, but I'm not a foiling boat so an extra few kilos won't make me look much worse than I am around the cans... And if it lasts 1/3 longer than the type II I think I could justify the cost...