When Hitec introduced it's magnetic inductance 7990 servo, several of us really old guys said that this was nothing new. Here is an add from RC Modeler, Jan. 1967.
I don't know it these ever made it to market since at that time you posted the adv. before you made the product to see if there was any demand.
In same issue, there are escapements, reeds, galloping ghost, and proportional AND the first 72 MHz system - Bonner Digimite 4.
EDIT: I think I see some of these in this picture on the left bottom:http://www.rchalloffame.org/Manufac...-1001-full.html