I use Painter IX (then Photoshop for cropping/exporting). Because Painter recognizes PSD, I keep it in that format. I have a cramped 1.1 GHz piece of shit computer. So a lot of the brushes (like watercolur) just drag for me. I like the acrylic and artist oils. But lately I've discovered the blender brushes which work really fast. So I block color in first (say with Illustrator) before I import it, and push the color around with the blenders