You only own one handgun? If I had to give up one of mine I have plenty more to choose from.
You need a duplicate because if you need to use it in defense of you or loved ones it will be confiscated. Do you really want to be unarmed with the friends and family of the guy you just shot upset with you?
Having something of the same manual of arms is much easier to transfer too.
Did you even read what I wrote? What you said makes no sense at all. My normal carry is a 1911 and I have a number of replacements just in that model alone. I will not go into the number of other firearms I have.
I disagree. I have two other pistols that I know just as well as my EDC. No one needs to spend an extra $500 buying an identical pistol because they might actually use it someday. If you are that dependent on one gun, just buy a new one if that time comes. Now obviously the Glock or 1911 obsessed may already have duplicates, but it isn't a need.