I aim for the same shot placement as I do with an arrow. A broadside shot, dead center on the height of the animal and slightly behind the shoulder blade/leg bones. I'm looking to place the bullet in the middle of the area containing the heart and lungs, both elevation-wise and horizontal-wise. The area bounded by the diaphram in the back, the spinal cord on top, and the sternum on the bottom and front. I just don't see any other location that offers more forgiveness of bullet placement error, as this centers the largest lethal kill zone on the animal. Done it this way for 40 years now; short-range, mid-range, and long-range. If the bullet has enough retained velocity to expand, the animal is dead. Another reason I choose this location is it kills the animals just as surely as a high-shoulder or any other type of shoulder shot, yet results in the least amount of bullet-caused meat waste / damage.
Now if I'm close to an animal with a good rest, I have head shot a few. It doesn't get any cleaner than that. But that's not a suitable long range aiming point from my persective.
The only reason I would shoulder shoot any game animal, either high or low, was if I was videotaping the shot for sale to the public. If the shoulder shot drops the animal in it's tracks, the taped kill could appear to be more humane to the anti's or uneducated. But the fact of the matter is that shoulder shot versus lung shot, the animals aren't likely to be brain dead any quicker one way or the other. It takes just about the same amount of time for the blood pressure to fall due to blood loss in both locations. My lung-shot game may move a little ways after the shot, but they're running dead on their feet.
I might shoot a bear through the shoulders if I needed to break him down up close, but even the three brown bears I've shot were taken with the broadside lung shot behind the front shoulders. The larger two both came off their feet at impact and never regained their footing. In fact the larger of the two was dead on impact. Literally. He squared 10' 5" and was hit from 130 yds (I'm not claiming long range) with a 225 gr Trophy Bonded Bear Claw from a 338 Imperial (equivalent to the 338 Edge). He dropped so quickly, and without even a twitch, that I thought I might have brained him. I couldn't believe a lung shot could put down a 1000 plus pound bear - instant lights out - like that. Because of these doubts, I watched and waited a good 15 minutes before even beginning to approach. About 25 minutes after the shot I was finally standing next to him, expected to see a head shot bear. But the bullet was centered in the ribs right where I had aimed.
I won't argue here with others about the efficiency of the kill between the high-shoulder hit or my lung hits. They will both produce humane kills. I'm happy with my lung shot clear of the shoulder. It's just as humane, offers a greater margin of shot placement error, and results in minimal meat damage.
Interestly enough, on my last brown bear hunt on Kodiak Island, while I was reviewing some literature produced by the Alaska Department of Fish & Game, I read their recommendation and preference for the lung shot above and beyond the shoulder shot, because a lung shot bear is a dead bear. The long-held belief that the breakdown shoulder shot is the preferred shot for brown bear is resulting in more wounded bears than a well placed lung shot, in their opinion. Shot's missing the shoulder bones are often not as deadly as shots centered through the lungs because of that lack of lung damage. I'm not saying that Alaska Department of Fish & Game biologists are the final word on shot placement, but they normally aren't too far off base either.
In fact, I'm not saying I'm the final word on shot placement for any of our other forum members either. But I am for me, and that's how I do it.