Thanks John,

No you don't notice a "wind tunnel effect" sitting between the sails.

There are no boards, or skeg, the hulls themselves are pure aerofoil shapes and they seem to work very well, no excessive leeway.
I will take a picture of them this weekend. We store the boat upside down on Brighton beach as the local scumbags like to use the trampoline as a trampoline and other nocturnal activities

We haven't been out in big winds yet so its too early to say how well it performs, its been up to 10knots in 10 knots of wind with 170kg crew and 14sq metres of sail. Next step is 20 sq metres of sail.

Gareth