I want one.
I thought about the heat as well. I wonder how a person would insulate under a concrete floor, other than an open area underneath the slab, such as a basement? Not easy to have a concrete slab off the ground.I only saw one problem. They didn't insulate under the heated slab. The ground is a massive heat sink that you can never fill. One guy around here put in a heated floor in his garage to save money and wound up spending more on heat because the earth kept sucking all the heat out of his uninsulated slab.