Co2 been widely used and just being rid of a noisy compressor. Not that my Emda make noise I can hardly hear it, but if it one day give up then finding another as good, will be expensive, --- so I prepared by buying a second hand reduction valve and then if the problem come, I must find out if to rent a bottle or buy one to get refilled. But Co2 is only "cold" when it is released from a fire extinguisher it's the expantion that make it cold and the volume used by an airbrush will not make any cold. Beside CO2 is dry, it contain no water but is heavier than air, --- could mean it work better than air, just wonder.