I'm relatively new to handguns, but over the past couple of months, I've accumulated three (an xd9, a gp100 and a ppk in .380). I was at the range today and I rented a full-size (5") Springfield 1911. I shot fairly well with it (alright, very well) and I'm contemplating getting one in the future, but I was wondering: I've read on this forum rants and raves about how great of a self-defense cartridge the .45 is, but from what I've seen, it has been outclassed by more modern cartridges like .40 S&W, etc., in both muzzle velocity and muzzle energy. Even the 9mm comes close in both those departments, as well. So what makes the .45 so special? Is the allure of the .45 simply the gun that is chambered for it (I speak of the original, the 1911, and its supreme wonderfulness) or is there some ballistic evidence that I haven't yet stumbled upon that solidifies the .45 as the ultimate handgun self-defense cartridge?