You cannot look like a woman with a beard on your face...trust me. I bet even the Bearded Lady at the circus has a hard time proving her femininity without dropping her drawers.
It is also difficult to appear androgynous (in the true sense of the word) with facial hair.
GenderF***ing, however, can be a blast. If done subtly, it takes people a few minutes to notice your makeup and nail polish and women's clothes...or you can hit them over the head with it (which always made me uncomfortable so I didn't do it too much). Somehow, the beard and the DDs just made me feel a little strange (and the looks I got made me think people thought so too).
Still...there was something about not even trying to pass that made things a lot easier...no pressure...no worrying about being read.
The biggest problem I ran into was (and still do sometimes, even without the beard) is that people see you as a feminine man and immediately tag you as gay. They don't see Androgyne...heck, most of them have never heard of it. If you are attracted to males, this may not be much of a problem. If you are attracted to females (or if you live in Redneck-ville), it can be a little awkward (and scary) at times.
My beard comes and goes depending on how I feel. Right now, I am in a beardless phase. It may come back soon or it may stay gone for a long time...only my hairdresser knows for sure.

....Laurry