Hey ok,
Here is a blatant self pimp. But it seems in regard to your thread, this is ok-ay?

Let me know if I'm over chalk line here.
I'd like the chance to make you that board.
I've been catering to a few of the local surf board snappers up Brunswick heads way using the latest resin and foams with Bi-axial cloth, stringers and carbon tape rails and stomp pad stiffeners. So far their problems have gone away. The boards are coming out 2 - 2.5 kgs without fins. (that's with a 6 x 4 x 4 on the deck)
With the extra laminations top and bottom that I imagine appropriate for the life of a kite board, that would bring the weights for a 5' 6" x 17 1/2 x 2 closer to 2.5 kg(no fins/traction pad) and 3kg for the 6' x 18 1/2 x 2 3/8" varieties. One variable will be that my foam supplier can only supply me the 'next lightest' weight of foam to what I have been buying as they are changing their business structure around and won't be running the super lights for quite a few months. I have one of the 'next lightest' ones in a heat box at the moment to dehydrate it a bit (they are formed with steam) but we'll see how it goes.
A couple of the kiters down this way I spoke to seem to think that the boards snap "from the bottom" , so they glass the bottom as heavy as the deck. I'm not sold on this line but if you have more info on it I'd love to hear it.
It's also worth noting that a lot of converted surf boards deteriorate at the join immediately between the strap plugs and the glass. This stands to reason that putting them in under the deck lams/veneers would eliminate at least one weak point and give the purpose built kite boards another advantage.
I agree with AUS126 that rock solid is the way to go for surf boards. Flex is totally overrated for your average surfer IMHO. It seems great for ramps and freestyle in TTs but for surfing - never did it for me, and toying with it is playing around at the edge of the realm of snappability. If you can afford the amount of boards Taj can, go for it.
Of the big brands the NORTH Wham is definitely way lighter than the Naish and Cabrinha equivelants by about 2 kgs. I wonder if it is as durable?
Cheers
-Johnny