I have 4 ZWave Controllers on the same network. I don't think that, by itself, is a problem.
I've had multiple ZWave Controllers on my network for years. Adding Hubitat increased mine to 5 Controllers, allowing me to remove two... but then I added in a 2nd Aeon Z-Stick to help me understand shifting Primary to the Hubitat Hub along with SUC and SIC. That same ZStick then assisted me in doing OTA updates to Aeon devices without having to remove (exclude) and then add them back (include) followed by a repair of the Automatons broken by the removal.
