Sorry, I forgot to mention that
I did discuss it with Kev and he told me the waterproofing will be done using the polartex. He's got a load of that in already and it would add to the cost of the shirts if he had to buy an alternative added to the extra time spent washing it in.
On the subject of washing he did tell me that he's washed the original demo shirt twice now at 30deg and there isn't any sign of shrinkage. The only time he's seen shrinkage with the blankets is occasionally they might shrink about an inch which on a 90" blanket is pretty neglible.
As for the options I'm going for the stacker kangaroo pocket and I really recommend this, Peggy and Kev have worked hard to get a really good design together for this option. It's neat and tidy and ideal if you want to carry maps etc. I'm also having leather trim round the neck closure and cuffs, cuff tabs and a breast pocket with flap closure