I would want it to be versatile, with possible use as a hunting gun, carry gun, and home defense gun.
I have long been a fan of the 1911 system as a platform for different calibers. One of my favorite blasters is the Colt Delta Elite, chambered for the 10MM auto. There are hunting loads and personal defense loads available for the 10MM. My favorite load is the 175-grain Winchester Silvertip, reliable and accurate in my particular gun, not the upper end of potential power for the 10MM but still very substantial.
Yeah, if I had to live in a one-handgun world, this may well be my choice. Then again, if the one-handgun world allowed me to keep a few rifles and shotguns I would probably choose a 1911 .45ACP over the 10MM auto.
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