Its hard to tell from this angle but he is definitely mature and legal so if you want to shoot him. I mean if your hungry, shoot him. If you haven't shot better, shoot him. If you have meat, have shot better, and will see him again... let him grow
That's kinda my philosophy on bucks too. But I'm on a small piece of land and I don't think we have a massive number of deer based on what I've seen so far this year.