I'm not a ballistics expert, weapons expert, bullet expert, LE expert or anything like that. Nor did I stay at the holiday inn last night. I do know a little bit about the public admin/MIL decision making process. A key part of the proccess is identifying and prioritizing evaluation criteria. This changes project to project and leader to leader. Guy A might say Factor A is most important, Guy B might say factor Z is. That will affect the outcome. GuyA might be right for his situation and guy B might be right for his. Your situation could be completely different. Think and act accordingly.
PAT, DR ROBERTS and many other people have already given us the answers and we just need to stop the squabbling and listen. DR ROBERTS has said the Shot Placement is the key factor, and PAT has continuous hit the TRAINING piece. IMHO use what you have, train hard and put the Bullet in the lethal areas faster than he can do it to you, and if you get shot along the way, DO NOT QUIT, CONTINUE TO KILL THE BAD GUY UNTIL EITHER HE IS DEAD OR YOU ARE.
Feel free to call me an A-hole. This particular discussion dosen't affect me much as I am stuck with USGI FMJ in 9MM,5.56MM,7.62MM,ETC. All of which can be down right lethal when used properly.