I finally settled on a Kappa
Cut 10-40 regulator 150% a damn fine headsail for most condition but a
light air sail it was not.

What was the problem as a light air sail? I should think a 150 would be
primarily for light air use.

My sail is 150%, for use in 0 to 15 knots of wind. What is a kappa cut
and why didn't yours set well? My genoa is for a masthead rig, I'm
likely to be getting a Twaron (like Kevlar) laminate genoa, straight
cut panels, and for a reasonable price in comparison to having a
similar sail (With Kevlar-branded Kevlar) for about £200 more.

My original question surrounded the use of straight cut panels (I know
they have 'draft' cut into them!) vs. a radial cut, which to my
uneducated eyes would seem to allow more of a 3d-type shape to be cut
into the sail. The sailmaker seems to think it makes little difference
in this material.

Any comments before I undo my wallet and cough up to my sailmaker?

Many thanks

Artie