Here is a 5 second face sketch with the skin tone Pitt Pens..kinda funky. If you hold it farther away from you (which obviously you (dear reader) can't) it looks even more like a face. I looked at the sketch on the front of the Pitt pen skin tone marker set pack (say that fast, oh 2 or 3 times...). Their pic is much better but not too bad for the first time, and in 5 seconds.
I would be willing to bet that my son could do much better than either one...too bad he is not here at the moment or I'd try to bribe him, I mean talk him in to trying.