I am thinking he is young, and I would hate to ruin a chance at a bruiser in the future. If I had no other choices I would love to stick an arrow in him, and I still have not counted that out. I just hope I do not have to make the decision while in the tree, because it would be a tough one.
I would say that deer is at least 3 1/2 years old, maybe even 4 1/2. Reason I say that is his waist is even with his chest.
I feel like he's a little older at 4. His front legs are wide below the knuckle, his neck runs lower to his brisket than a 3 and his rear end is rounded over. His front shoulder is also about level with his rear end rather than taller like a 3 or shorter like a five. Very nice buck.
At the 3-4 range, he could still put on some good inches before he tops out and starts going the wrong way?
Yes, very easily. I'm not familiar with the deer in your area of the country but here at least they are just starting to come into their own by 3-4 years old. First year antlers don't mean squat, second year antlers will give a slight hint as to form, third year antlers set a tone, fourth year antlers pretty much settled in as far as shape and general dimensions, fifth year antlers generally gain some finishing touches in mass and dimensions, sixth year starts to gain any stickers or abnormalities (character), seventh year is a toss up depending on condition of the deer but can change configuration some sort of stay level with year six starts showing some age character, year eight will get a melting waxy look to the antler shape and go downhill from there.
I'm not the greatest judge when it comes aging a deer, I'd guess 3 1/2 - 4 1/2... 3 1/2 being the youngest and 4 1/2 being the oldest.. It's clearly not a 5 year old deer or a 2 1/2. I would personally shoot that deer as is, regardless of age, but then against deer like that don't come around too often in my parts and chances are someone would shoot him if I let him pass.
I see a 3.5 deer and this is my thinking: Pronounced brisket (usually 3+), hind is not jacked up (seen on < 3), no sagging belly (4+).