Depends on the paint layers. Sometimes for me, when I\'m glazing or something, the paint pretty much dries not to long after hitting the mini, even with retarder. When putting a good opaque basecoat down, I usually have to allow a lot more time for the paint to dry.
Haven\'t really had too much problems putting brush strokes through previous paint layers, but it probably has a lot to do with where you are and what you\'re using.