The downside to suction brushes is you need to run higher pressure than a gravity fed brush. Professionally you find that in general, airbrush artists working of hard surfaces use mainly gravity fed brushes, and those working on fabric or canvas mostly gravity fed. The Airbrush artist Mike Lavalee had Iwata make him a 0.3mm brush with a larger cup for less refills doing large surfaces for his true fire. If you are also planning to use an airbrush on your boards and you are selling them, do not get a cheap brush... once you have felt the performance difference of something like an iwata or richpen, you won't want to go back.