Dave Robelen comes to mind, I think he was the man behind Airtrol.
Their Cessna 150 looks to be the best of the lot for Galloping Ghost.
Airtrol Pulse Proportional systems used a Controlaire SH100 receiver. They made their own lightweight actuators that Dave designed and built, allowing them to be flown in 1/2A planes down to .020 size.
They had a rudder only, rudder elevator, and REM pulse systems. Interestingly, most of their Ghost systems lacked a trim for rudder, they only had elevator trim. They also had a fast pulse dual actuator set-up, and it was called the Digi-Pulse, but there was actually nothing digital about it: pure pulse proportional, single channel. I seem to recall they had a rudder only set-up, that came with the plane and engine. I saw one flying in a schoolyard when I was in my teens.