If you're going to be doing a lot of painting you should invest in an air dryer. It goes inline with the supply valve and takes all of the moisture out of the air so it doesn't get shot out of the other side. Look for a compressor that can do 90+ CFM . Most paint guns will have different CFM requirements at different air pressures. Different paints require different pressures. The longer you spray the more air you're going to need. If you never go above 90CFM and that's what your compressor is rated for and it's constant duty then you'll never have any problems.