Fabulous and fascinating handguns, not least because of their versatility. I often carry mine with the first two up being rimfire for small varmints around the place, the rest Jets for bigger or further away critters such as coyotes. I don't wear ear protection in this setting, and the Jet's muzzle blast is Biblical, hence the first two being .22's. I did have to practice under a timer to instill pressure to remember to flick the firing pin selector. My 53 with inserts is actually more accurate than either of my K22's or my 5" 63, which puzzles me given the former's long jump the rifling.
I'm only half kidding when I suggest that American law enforcement transition to the M53. Easier and cheaper to train recruits (many of whom these days have never even held a gun until the Academy) due to low recoil and blast. Knowing they only have six rounds would help slow down what sometimes becomes "spray and pray" in actual gunfights. The M53 reloads faster than any other revolver due to the relative ease with which those .22 bullets go into the back of the .357 chambers. While the blast is horrific the recoil is very light. And those narrow, wicked, fast bullets will penetrate a lot more armor than any other commonly used pistol round (yeah, that can be important; we are seeing more and more bad guys wearing armor to commit robberies and mass shootings). If a .223 is effective at 300 yards (and we can argue that point) then the Jet is effective at the close ranges most police gunfights happen. So there.