a very expensive alternative to a plaster cast ...and the rapid-protype material will probably have issues with water, uv-radiation (sunlight) ...
over a two-month period ...
All true, Patton@Bastogne, and there are probably additional problems, but that's the nature of bright new ideas: they take awhile to develop. I'm sure the weight savings alone—once the numerous and various bugs have been worked out—would more than justify the expense and bother.