ORIGINAL: Sport_Pilot
The Cline and Iron Bay regulators are non adjustable demand regulators, they deliver pressure at or just below atmospheric pressure, so there is no issue of the idle circuit being too sensitive. The Perry Pump has an adjustable pressure regulator. It is also porportional but probably has a wider throttling range (predictable error).
Sport Pilot
I understand that you are not familiar with process control systems.
Cees