So your running from a horde of zombies, you come across an abandoned military building. You get in but soon realize the place is not abandoned,you need to get out of there! There's a small table in front of you arranged with almost every type of semi-automatic handgun in the world. You don't have any where to put the guns so you can only take one or two.So which gun do you grab to get out of there?
Me? I'd go for a Socom SOCOM Pistol Mk 23 Mod 0 .45 ACP. Why? Well because it's compact,comes standard with a laser and silencer,has an extended clip,and in my opinion .45 ACP is one of the best rounds it's big,has decent peircing power and does'nt have to much kickback.
I've fired the Desert Eagle. It's a big beast and can get the job done but for an everyday piece I'd prefer something that weighs less then the boat anchor of the Titanic. Any gun you can use to help is going to work. My biggest issue with the DE is space and size. If I was going with big guns I'd prefer the H&K USP .45 ACP. There are a lot more .45 USP rounds out there then .50AE. Hell if the only weapon I had was the Jennings .25 ACP I'd use it. When the shit hits the fan and the world is screwed whether it be worldwide natural disaster, zombie plague or total economic collapse you protect yourself with what you've got. Oh, I also have a Jennings stashed away as a drawer gun.
A .45 really isn't much smaller than a .50 5 hundredths of an inch is pretty small. As for dual hand guns, HA!!. Seriously to get any real accuracy, which is needed to to score a clean headshot, you will need both hands.
The table would be a better bet, elsewise, you would want the lightest weapon with the biggest magazine that had ammo that would pierce a skull. Your humble twenty-two would serve here.
Your handy .22 will not work here. It's unreliable for skull piercing. All those stories you've heard about bullets ricocheting off someone's head...that was a .22.
What .40 (my favorite cal by the way) I have a Springfield XD sub compact that everyone seems to love, I've been goig back and forth between that and my M&P.