Air Fittings

I dunno anything about "purple" fittings but t use a Milton P style. The typical standard ones are Milton M style.
The butt of the "m" fittings will fit in the end of the P fittings and yes I definitely noticed a huge difference in power especially on things like my impact wrench. Not so sure it would be any effect on something like a spray gun. The only thing is the bigger longer fittings can be a little unwieldy in tight quarters.