There seems be two different opinions of these boats. One is they are very cool. The other is that they have very limited use.
I have made one and gave it away as it did not get used. They are a very specialized boat. The behave very similarly to a white water boat. Not exactly something that will go strait for very long. In addition, they sit very low in the water, not like a 10 ft recreation boat, but like a white water boat.
So as you can tell by now, my opinion is that they are too specialized to be general use. If Morris had only designed a 11-12 ft boat with stems deep enough to track well. Of cource, what I just described is easy enough to do yourself.
As far as using found materials, the materials are quite cheap when purchased yourself anyway. I would love to try willow and actually have a tree growing in a pot specifially for this purpose. In about 5-10 years it will be big enough to harvest.
Scott