Our local cop department has gone back to Glock .45 cals for a number of reasons, including economy. Also, the lack of an external safety and 2/3's pre-cocking provides a distinct speed advantage. Parts are cheap and available everywhere.
I boiled my decision down to the .340pd and the Glock 26. I'm not carrying 99.999% of the time but did want something reliable, able to withstand abuse and dirt, and be effective. One big factor that brought me around to 9mm is the huge variety of ammunition choices, some as effective as .45 white box. Glock doesn't limit what goes down the tube, like some manufacturers. Second was economy....9mm ammunition is half the price of everything else, meaning, I'll take the arm to the range much more often. It's available world wide. The Glock 26 is 8 oz. heavier than the 340pd, no doubt, but you get double the chances and the new price of the weapon is now about half of the 340pd (scandium must be like gold!) I've run 200 rounds through the Glock....it's almost boring...the thing just works. It weighs exactly the same as my .380 Colt...which has 6 chances. I considered the Glock 35 (?) which is .45 in a 'baby Glock' frame, but decided 9mm would be more controllable in a small chassis.

One other 'fun' ultralite option is an NAA Blackwidow as a plinker and small game piece....and as a carry option, although down the list a tad. You get serious accuracy with .22lr OR .22 mag in an 8oz. frame. I know a sheriff deputy here who carries one as a BUG. Anybody own one?

Anyway........
I really appreciate all you LEO's offering your input here. It's an important subject and comes up often. Again, this thread is not about IF, it's about WHAT, and you guys dealing with it 24/7 have the best perspective, by far.

Dryer, I understand your choice. I'm like slohiker in that I agree that something is better than nothing. If price is an object, S&W makes several light weight revolvers that are only like 3 oz. more than the 340PD like the 442+P or the 637+P. These are about half the price of the 340PD. I guess when I'm out in the woods I have other things on my mind (like fishing) and don't want to worry about making sure that my weapon system is maintained. Also my wife has small hands and wrists and can controll the recoil on the 340PD with 38+P loads. People with small or weak wrists need to consider that before choosing an auto.