I use this with all my acrylic hobby paints including Games Workshop ones. I put a couple of drops in airbrush, then put the paint in the cup, a tiny burst of air/paint to push some flow improver through and then cover the nozzle to back flow and mix the paint (so it bubbles in the cup). It really helps achieve the right consistency and prevent blockages. I've got a temperamental airbrush that was constantly giving me problems and this has almost entirely eliminated the issues I was having.