Back in the 90s a pair of guys showed up at a Tucson contest with one of these systems. They were marketing the system and had a few for sale. They set up a demo circle across the park and flew it off and on all day. It was a smaller model, .15 or .35 powered. It flew pretty much like a sport model-I doubt it was trimmed very well.
I walked over to visit and take a flight. My thoughts were that it was novel, had potential as a sport flying system but I couldn’t see any contest applications.
My biggest critique was the control “mode”. The control was a stick anchored to the ground by a low lawn chair. Ergonomically it was actually set up quite well. Reminded me of a side stick controller in the F-16. Pull back away from the circle for up and forward towards the circle for down. The stick had a spring to provide artificial feel but the spring was only one direction-down. There was no center or neutral position. You had to constantly maintain back pressure regardless of elevator position. Go up? Pull back. Go down? Pull back less.
My first thought was if they had springs pulling both up and down, and the neutral position could be adjusted to “trim” for level light it could be a reasonably realistic rendering of traditional flying.
Apparently they did not implement my suggestion as I’ve never seen another one fly and I haven’t received any royalty checks. It’s been almost 30 years…I’ve given up on the checks.