Here is a quote from the company overview:
"proprietary custom blend of high tech, high grade, PolyUrea called Rockard®, an extremely resilient, elastic material, used in many high stress applications. For optimal insulation, we use a filling of PolyUrethane, to give 6” (15.25cms) thick walls, for an insulation value upwards of R42. "
Yes shipping would be an issue but they are planning on setting up Plants/Factory internationally given enough interest as the it would be cheaper for both parties.
The cost of a basic unit in the USA would be about 20,000$
From the looks of it the pieces fit snugly together and there is no seam. Also the pieces are light enough to be carried by one person.