I actually really like the 1/2 MOA adjustments for anything short of a true target gun, maybe a dedicated long range varmint rig as well. I'd actually like to see some 0.2 mil adjustment scopes hit the market. I've always thought 1/2 MOA adjustments would be perfect for a hunting rig.
With 1/2 MOA clicks even at 500 yards the most you are off your aiming point is what +/- ~2.6 inches that's not much. Most AR's won't shoot 5" groups at 500 yards anyway.
Essentially you are trading some precision of the scope for speed and ease of adjustments. Most 1/2 MOA scopes can get you to 600-800 yards in a single revolution. 1/4 MOA scopes are going to need multiple revolutions and take longer to adjust.