I thought it worked pretty well when I used it, the main advantage over other packages being that you have access to all of Photoshop's brushes and features - which personally I think are much more powerful than those in Bodypaint. Photoshop's brush engine is much more powerful. The main drawback is that in Bodypaint you can paint on multiple channels at once (like diffuse and bump together), which you can't do in Photoshop.
