Personally I add cellulose thinners to enamels as it dries quicker, also I find that I can get better results with enamels for spraying mottled finishes as acrylics dry TOO fast and clog the airbrush, even with retardent. I managed to get a squiggle line camo on a 1/48 Me262 with Hannants enamels, something I could never get with acrylics.