Only the bottom one is still growing much.
I can't really determine much about the buck's age in the top pic, other than to say am reasonably certain he's 2 1/2 or older. Good chance he could be 3 1/2, but I doubt any older than that.
Can't really see enough about the bottom buck depicted to guess age.
However, the amount of basal antler mass is highly suggestive he's 3 1/2 or older, although he could easily be 2 1/2 or 4 1/2.
Need more pics
The bottom buck is going to have a relatively short-tined rack, as his G-2's are already essentially finished growing. For most areas of TN, he would have an above average width. He'll likely be easily identifiable in the field, wide rack, shorter left G-1, short G-2's, and may have a "crab-claw" configuration with his G-3's.
Assuming they were the same age (likely not), the bottom buck would be the better "trophy" rack to me, simply because I have a greater appreciation of more unique features. Most antlers are going to have longer G-2's than G-3's, but believe this one is going to end up the opposite. Plus, his G-1's don't match up as much as most, just making him a bit more "unique".