Always go with the lungs shot. Think about it, if YOU can't breathe, how long are you going to last? Not very. Give the animal it's time to lay down and expire after the shot, don't need to push it. As far as ammo, I shoot Hornady BTSP in 162 gr. Rem. 7MM. I use core-lockt with my .35 remington and love it, works great on WI Whitetail. Use what you feel works best for you and your gun and stick with it. We all have different ideas and approaches to things, but, if you stick with what works, punch a hole or two in the lungs, you will be punching your tag. I agree with the others...you can sacrifice a rib or 2....good luck!