My personal choice is Winchester Ranger for use it in my 9mm (+P+) and 45 (+P). This is the same ammunition that is issued to the NHSP. There is a documented shooting in NH of a LEO having an up close and personal with a BG and he had to make his shots through a refrigerator. Now this is something that could definitely happen in a home defense situation. All round passed through the frig and stopped in the BG. These rounds also stop in the BG without having passed through nothing more than clothing. The NHSP tested the 40 and regarded it "not as reliable a man stopper" in the most common bullet weights so they do not issue 40 caliber pistols. Most projectiles are too heavy to get up to the required velocity for proper expansion. At the time there were not many loads in 40+P so they may revisit this caliber in the future. They do get to that velocity when the projectile weights are under 155gr. One NH Trooper I know said that the best ones, of any manufacturer, are in the 135gr range. Anything over 165 will be too heavy in a compact 40 to get up to the needed velocity. Once he told me that, and I trust this individual greatly since he was in on the testing of weapons and ammunition for the NHSP, I switched to the lighter rounds for my K40 since it is such a short barreled pistol. Of course all the above is just my one cent worth.
IMO bullet placement will go much farther in dealing with a "SHTF" situation, two quick ones, center mass is going to ruin someones day regardless of caliber or whether the projectile expands.