So my one of my sons is just coming of age to play paintball and really wants a new gun. I still have my minimag lvl 7, but haven't played in about 20 years. I used to run CO2 on it but was never really happy with the way it ran. Looking at getting a HPA tank to use but not sure on the right pressure or size to use. I see 3000 psi and 45000 psi, yet the rated psi for the valve on the mag says "rated for 3000 psi". Does that matter? I've also heard some guy at a shop say not to use HPA on a Mag because of the pressure output and to stick with CO2 (didn't agree but am not knowledgable enough to counter). Any help would be great.