Glock 19 Gen5 MOS. Ambi friendly, no finger grooves, better trigger, better finish on the slide, better barrel, rounded nose on slide, and slide milled for optics.
I too would limit myself to the G19. Counting military, and police sales, I think it's the world's best-selling 9mm.
When I laid my G26 atop my G19, I realized that the size difference was mostly in my eyes and the two guns were so close in size that I sold the G26 and never looked back.No gun will have the honor of residing in my safe if I need a magazine extension to get three fingers around the grip (middle, ring and little).
I'm the same with semi-autos. I want a good 3-finger grip on the front strap. My PX4 Compact allows me such a grip with the standard mag. Had a Gen 3 Glock 23 that fit me well in that regard.
Of course, I do have an interest in getting a pocket .380, which won't allow for a 3-finger grip on the front strap, but I see it as a "special purpose" tool, so I'll relax my requirements for that one.
I only own 2 Glocks. My former NOPD Glock 22 is at a friends on extended loan. My GGP17 I own only because I wanted a handgun to go with my Glock pattern AR9 braced pistol that used the same magazines. Had a lot of fun putting it together and I like the improved ergonomics of the newer Polymer80 style frames.
When the FBI went to the 19M 9mm a couple of years ago, my wife gave me her 23/27 .40. She carries a 26 now for her POW. Not too sure why the bureau went to the 19M 9mm, probably had something to do with $ and recoil, but it's ok by me because I now have a couple of great carry guns in a caliber I like! Here's my BBQ Glock also a 22/.40.
I went to a firearms instructor school last fall. The majority of officers there had newer model 45s and every single one said it was their favorite Glock ever. I few said they didn’t know why but they shot the 45 better than a 17 and a 19.
Either a 19 or a 19X. For the 19, it would be a gen 5.
I own both, and they have both been flawless shooters. It would really just come down to whether it's a gun I want to be able to conceal somewhat, or if I'm OK with the full size grip.