Looks like there is only two Blades sailing in OZ and one of them is a home build.
What is the distinction between a home-build and a prototype ? Actually both are prototypes, were the mark 2 is a refinement of the mark 1 (first) design. This way they're are honing in on a good design.
I wish Matt had gone with the 18 instead of the 16.
Why not go with both ? Wait a while; progres may be slow but it is certainly there. Personaly I have much faith in such an approach. You need sufficient time of testing and evalution to get the product just right.
Wouter