I use Nitrogen that I get from my welding supplier. The tank rental is $5 a year which covers inspection and certification (required by law to have it filled), the regulator cost $45, and to refill the tank cost about $20 and a tank lasts me about 2 yrs or several dozen models.
I don't have to worry about moisture, Nitrogen is inert so it won't interact with solvents, unlike compressed air, it is not under high pressure so there isn't a risk of a tank rupture, and the tank is quiet, portable, and keeps a constant supply of pressure.