I have a feeling that you should look neat/clean at your interview. I don't see anything wrong with facial hair provided that it is well groomed. Think about it. If a doctor has a gross beard (as in dirty or messy), then would you want him examining you?
yeah, i'm normally too lazy to shave, but when it comes time for an interview, my facial hair just falls off, i don't even have to tell it to, it knows what to do