I meter my cabinet with the air pressure going to the gun. More aggressive media, like 80 aluminum oxide, I turn down to about 80 PSI. My soda blaster I run at full speed, at 135 PSI. For delicate things like alternators, I use organic media, like walnut shells, and adjust the pressure. I have a big 80 gallon 2 stage compressor, so my options are wide open. My cheap HF in line filter/dryer helps, as the weather up here is usually high in humidity. YMMV.