Issued a SW99 .40 S&W (uniform) and a 6906 (plainclothes). I'll often carry the SW99 for my plainclothes assignment, though. The 6906 is just a bit more controllable during training because of the caliber, as well as a bit more comfortable (concealed) during long shifts involving sitting in the car, and getting in & out of it all day.
While I've often carried the SW99 & 6906 off duty, I more often carry one of my own weapons off duty. Mostly it's a 642, which is smaller and easier to carry, and fits many of my off duty activities better. When I want something larger (and with more capacity) I generally tend to carry either one of my compact S&W 9mm or .45 ACP pistols, or a G26. (I also own a G27, but it hasn't yet seen any duty outside the training range because I simply prefer the G26 in just about all respects.)
I also tend to miss my earlier revolver days. I still qualify with a couple of my .357 & .44 Magnum revolvers, even though I seldom carry them anymore. If a day in the backwoods is planned, which isn't nearly as often as I'd like nowadays, one of my medium/large caliber revolvers gets the nod.
When I retire in another couple of years, and move to somewhere farther outside the urban areas, I wouldn't be at all surprised to find myself carrying one of my 1911's or a big bore SA revolver again ... except for those days when my activities make a 642 or little 9mm subcompact a "better" choice.
While L/E will no doubt continue to get more deeply involved with various medium & compact sized pistol platforms, I wouldn't be at all surprised to see a resurgence of interest in large bore revolvers for personal defense/concealment needs among legally armed civilians.
Sorry for getting a little side-tracked.
I really do miss carrying one of my earlier 4 5/8" barreled .44 or .45 Colt Blackhawks.