When to use water pressure regulator on fiver?

I use a pressure regulator every time.For just an overnight stop,I use the cheapo preset one,for longer stays I use the Watts adjustable (from the RV water filter Store)set at 55 lbs.
Using the Watts you get more water volume that using the "cheapo"

BTW don't fool yourself thinking that you can just turn the outside spiget down to reduce the pressure.It doesn't work that way.