Late night / Early morning sketches

Here are 4 other heads I just did.same thing as previous, drawing the 4 heads at the same time, switching between them every 3-5 minutes?
this time it took me about 1 hour to get to a satisfying point.
( an animated gif is once more on the way)



(click on picture for bigger view)

hope u like it (ps: if its to dark, adjust your monitor, yeps we all hate monitors)