Funny, I've watched that how it's made video a few times. It was much simpler than I expected. Each step has been worked out and in some ways I'd say the design is easier to make than conventional speakers. More involved steps in a sense, but only since you get drivers shipped to you ready to plug in for conventional speakers. That Jurgen Reis is one smart cookie too.
Never had the pleasure of hearing these. I wonder if Harman has ever done a listening test with them? I suppose someone could just assume a perfect flat response and plug the result into the formula to tell us how they'd score being omni's. In real life they wouldn't be quite that perfect and would score less.