Happi, so you're still looking for a new boat. Boy, I sure wish you could try out an NC 15'-8". If I didn't already have all the boats I need, that would be my next boat.
I haven't tried one out, but I think they would fit just about as well as my Expedition. If they are even a fraction of the boat that the Expedition has turned out to be, it should be an extremely nice boat. And by the way, the pictures don't come close to how attractive these boats are.
I guess the main reason I brought the 15'-8" boat up, is that you mentioned that composites are more expensive than thermoplastic. That might be true generally, but not so much in the case of NC Kayaks. Their boats are sold factory direct (not through dealers), so even though they are a very high end boat, the price is very competitive with even thermoplastic boats.
I've had enough experience in my Expedition now to appreciate just what the boat is capable of. Frankly, I don't think there's another boat that I would be as comfortable in nor feel as confident in to handle any conditions. I was out yesterday in some very rough confused waves that probably would have caused a lot of apprehension in a lesser boat. The Expedition went through it like it was nothing. I didn't have my spray skirt on and still, not one drop of water got on me, or in the cockpit. The stability is fantastic and the ability to just relax and let the boat take care of tracking is something that almost spoils you for most other boats.
I know I sound like a salesman for NC, but I just think that serious kayakers deserve a boat of this quality and I'm so happy that I became aware of them, before I bought something else.