Most men I come across with beards don't pull it off as well as they seem to think. A low, neat shadow can be very flattering depending on other features.
Too clean shaven looks infantile and the shaggy look only sort of works if you're young and overall have an edgy style (whatever that means around here). The full forest looks ridiculous to me, especially on men I might otherwise find attractive if I could just see their whole damned faces.
Ultimately though, try out a few looks and see what nets you the best response. It's just hair.