Thanks everyone, I appreciate all this wealth of information!

I have sent an e-mail to Calncy Arnold requesting some technical and commercial info.

BTW, does using his system require insulated wires and if so are they significantly thicker in diameter and does this mean they need to be shorter than when flying the same model size with "normal" lines?
It does seem that electronic control is simpler.

I used to fly stunt many years ago (mid seventies), and have concentrated since on scale RC.
I will probably first build a simple 2-line stunt model just to get back into things, but my scale interest will probably eventually lead me to scale CL models.

I have some 30-40 year old plans for 35-46 stunt models, some I have never built, and it should be very interesting to go back and build them...