Hi guys - thanks! I, too, bought the polyester fabric from George Dyson - it's nice that I can just walk into his shop while I'm still here in town (Bellingham, WA).
I like it so much that I don't plan to ever skin another kayak in anything other than this 9oz poly. Sewing it is easy, as you absolutely don't have to pull it drum tight. In fact, if you do pull it too tight, you just make large holes where the thread goes through. Once the skin is sewn up, run an iron across the whole skin and it will tighten up just great. Got a persistent wrinkle - or ten? A carefully(!) used heat gun will eventually completely remove even the worst of them. DON'T leave the iron or heat gun in the same spot for very long!

The polyester might not be quite as puncture resistant as nylon, but that has never been an issue, so far. And, polyester will retain it's tension, unlike nylon which sags and gives your boat that raisin look when it gets wet.

Tom will be posting the specs for the Rolldarka pretty soon. I should mention that this boat is the "LC" (long cockpit) version, and that it is 16'9" long, rather than 17'9".

From my limited trial, the boat paddles great. It has a different underwater shape, and about an inch more freeboard and beam than my old Sea Rover, and is noticeably more stable. Secondary stability is vastly better. Also, this boat carves turns when you lean, which the SR did not do, at all. It seems to be very fast . . . .
I can still lay all the way back on the rear deck, too, though my butt is off the seat. I suspect it will roll just dandy - I'm looking forward to finding out, as well as finding out how it handles in waves and wind.

The jury is still out on the oil based paint. It seemed silly to be adding oil based pigments to oil based varnish (ZAR) to make what is basically oil based paint. So I just used some of that, instead. Seems kind of soft to me, though, right now. It is likely that it will cure a lot more over time, but it might not. I'm not recommending it, yet, but so far it seems to be working, and it might get better. There are different flavors of oil based paint and I think I picked the one least likely to be suitable (it has linseed oil in it).

Thanks again!
Dave