I always will go for the double lung. A double lung insures the animal will not go any further than 50 to 100 yards. Both lungs collapse, the deer runs, passes out, then expires. I have never had any run more that 75 yards with a double lung. My brother took a shoulder shot once that caused us to track for over 2 hours. He hit it in front of the shoulder, missing most of the lung. If you put your pin/cross hairs just behind the shoulder blad, it is a done deal. I respect the animal too much to allow one to run off wonded.

I guess this would also depend on what you are shooting. With a pistol or bow, I always go for the double lung. With a rifle, I feel I have more room to play with.

As for head and neck shots. Too little a target. I always teach new hunters to go for the highest percent shot. Better to let an animal walk than to wound it. Head shots I refuse to take. I dont like the idea of blowing off the lower jaw of an animal, causing them to starve to death.