Just my opinion but I think you would look much better clean shaven. You are young and have great facial features - why do you want to divert peoples' attention away from that and to gray hair on your chin? It doesn't make sense to me.
You look older with the gray stubble and you look kind of sloppy - like you really don't care about your appearance. Cleanly shaven you advertise your self confidence and that you care about your personal appearance.
Just my opinion.