Fascinating thread - long, but I enjoyed going all the way through it. I'll just share my experience. I'm 78, have 16 or so handguns, and ten of them are .380's:
Browning 1911-380 Black Label
Beretta 84F Cheetah
Beretta 85F Cheetah
Beretta 86B Cheetah (tilt-up)
Ruger LCP Custom
Bersa Thunder 380
Sig Sauer P238
S&W M&P 380 EZ
Taurus Spectrum
Walther PPK/S (S&W)
They don't all get fired regularly, but they all get to the range at least once a year, followed by a thorough cleaning. I use ordinary brass-cased commercial PMC or Fiocchi or Federal 95-gr. FMJ ammo or 95-gr. reloads sold by the range. I've been well aware of the possible results of loose grip or limp-wristing automatics for many years, and I can't recall any malfunction incidents with any of my guns. I've never tried any steel or aluminum-cased ammunition in any of them. The P238 is my favorite carry gun, and I bought the 380EZ for my wife (70), who has had carpal tunnel surgery on both hands after 30 years on a GM graphic illustrator's drafting table and arthritis, which limits her hand/finger strength. She uses a two-handed grip and has no problems. We both have our CPL's and have taken several rounds of handgun refresher training.
I also have a .45 Long Colt SAA replica, a couple of wartime Walther P.38's, several 9mm Berettas, Bersa Pro 9mm, an S&W 5906 9mm, and five different .22's. Gun enthusiasts and always learning.