I can't imagine a meal I would want to keep hot continuously from lunch to dinner and still enjoy eating it. Maybe there is some, but not many. Plus the safety issue, once you have opened it to eat lunch it won't be all that hot by dinnertime. You have to maintain a certain heat to avoid bugs.
As far as actually cooking the meal in it, seems like a pressure cooker would do the same thing, minimal use of energy to cook the intended food. Just put the food in, heat until pressurized, then let sit until it's done. Wrap with a towel if it's going to be so long that you need to insulate it. Or use a crock pot for longer meals, and wrap in a few towels.
If I knew someone who used it regularly and could explain why it's worth having I might be open to the idea, but I can't think of why I would want it at this point, especially for $180. (I'm at work so I can't watch the video, maybe that would help...)