Back in 2007 at the end of May I published this article from Steve
Pearson about the durability of laminates:
http://ozreport.com/11.104#1.

All modern sailcloth and laminates include UV stabilizers and
coatings in the construction. For laminates, supplemental coatings are applied
between the layers below the upper film ply and are somewhat effective at
protecting the scrim and lower film ply. Unfortunately, they don’t protect the
outer film layer.

Dimension-Polyant develops and produces an incredible variety of high-tech
fabrics for the industrial, sporting goods and sailcloth markets. Last year, my
technical representative mentioned an industrial polyester film that is
molecularly altered to be ‘impervious’ to UV deterioration. Also, it stops 90%
of UV thru-transmission so it’s more effective than coatings at protecting the
other laminate plies. The only problem was that it seemed prohibitively
expensive—20x more than untreated polyester film. Fortunately, the film price is
a fraction of the laminate price and I decided that, even if the film was only
50% better than standard film, I could easily justify the extra cost. It’s
important to note that film color is not related to structural properties. The
common ‘smoke’ laminate is conventional polyester film. Our UVM material is grey
because the minimum order quantity for a different color (like white) of this
special-purpose film is 20,000 meters. According to Dimension-Polyant, the Wills
Wing UVM laminate is the first application of this film in sailcloth.

Now Steve Pearson writes referring to his earlier article:

We don’t recommend woven fabrics on T2s.  I’ve significantly
increased the VG tight sail tension to the point that permanently stretches the
woven fabrics, and because the UV laminates have shown to be as durable as
the woven fabrics.

Our confidence in the durability of UV film laminates is a lot higher now, and
the newer generation gliders can be configured with much higher sail tensions
for low twist and still retain good controllability and longitudinal stability.
These high sail tensions require stiffer/stronger laminates.

Woven sailcloths still fly better when wet and maybe somewhat more resistant
to some types of wear and tear, but I do now think that UV laminates are by far
the best choice for T2's. We're still recommending woven sailcloths on Falcons,
Sport 2's and U2's because the sail tensions aren't as high and the gliders were
developed around the stretch characteristics of woven sailcloths. I'm working on
adapting laminates to them.