Yesterday I was airbrushing the new vallejo primer on my T-34. I had heard people say they had issues with trying to clean their airbrush after the Vallejo paint had dried. With that in mind, I gave Simple Green a shot when I cleaned my airbrush. Oh my gosh, after I cleaned it with that stuff my airbrush almost looked brand new!
Haven't tried it with other paint brands, but I can tell you that this stuff works.
Brian