You just can't get air too clean and too dry. I have 3 compressors that feed into one of these for the shop air. http://www.google.com/products/cata...;resnum=4&ved=0CD8Q8wIwAw#ps-sellers

And then I have one of these for the paint gun.

http://yhst-13811118617756.stores.yahoo.net/dev-dad500.html?productid=dev-dad500&channelid=BCOME

A desiccant dryer is the best for final drying before the spray gun. I use the same system for a plasma cutter and it is almost unbelievable how much it extends the life of the consumables.