According to the manual for the water pump in my 19RD. The cutoff pressure is around 40PSI. Generally water pressure regulators for use at campsites are set for 40PSI too.
There is a HUGE difference between low pressure and poor flow. Once the pump turns off or the flow from the outside spigot stops, the pressure inside your RV's water system is equal throughout.
If one or two faucets flow well and another is poor. You have an issue with just the one. Unscrew and clean the aerator. Then start looking for kinked lines if that doesn't help.
If all faucets are bad, then the pump, pump screen or city water inlet are suspect and should be cleaned, repaired or replaced as needed.
TT 2015 19RD "TheJayco"
TV 2003 F-350 "Montblanc" - Housebroken chore truck
Sitting in The Cheap Seats.
And proud of it!