i'm one of the few unfortunate guys that don't look good with facial hair, and do look a lot younger than we actually are :/ i'm 21 and still look 17 at times, when walking down the street on a weekday, i've had police actually stop me and ask why i'm not in school lol
when i do go without shaving for a while, it always grows in a mix of blonde and black, so it looks like i have patches missing
fortunate for me, i dislike the feel of facial hair, so its a non issue