What am I going to do with it? Without that information, I could not choose.
For my purposes (personal defense) I have settled in to the Glock 19, with multiple guns, magazines, spare parts, .22 conversion kit, holsters, etc. So I suppose in real life I have already chosen.
1911. Not much I need done that can't be done with a 5" 1911. There was a time when, other than a .38 snub nose, it was my only handgun.
I carry a Sig P220 now, though, as my department is scared of SAO pistols. Not sure what makes a DA/SA safer. I never forget to put the thumb safety back on with the 1911 but remembering to de-cock took some training.
I agree it depends. If I could only have one handgun today it would be the Glock 22, it can easily shoot 3 calibers. It is relentlessly reliable and dont forget the cool factor.
If I could only have one handgun in a post apocalyptic world It would be a Ruger Redhawk in .44 mag.
Mine would definitely have to be a glock 19. Very accurate little guns but you can still conceal them to where no one can see them. Plus Glock's name speaks for itself. The most reliable guns on the market. I would never trust my life to anything else.