Are there any consumer test reports of the in-line 'regulators'? I can see how they can easily regulate flow, but regulating static pressure in your system when all the faucets are closed is much more difficult. I have plant equipment that requires a 20 p.s.i. water supply, and to reliably control the pressure takes a filter, adjustable regulator, and a pressure relief safety valve. I'd be tickled if I could replace all that with a $12.00 RV accessory.