Smith & Wesson's centennial frames for me. I just never warmed up to the Bodyguard frame's bulbous bulge (the classic model, not the polymer hybrid 38 by the same name) despite it's advantages over DA / SA J-frames. No hate, just not aesthetically pleasing to me.
I shoot my double action revolvers...well, double action. Even the ones with exposed hammers. Always did.
Both the Centennial and Bodyguard can, in an emergency, be fired through a pocket (not recommended - might light up your pants/coat pocket) and can be pulled faster due to no exposed hammer catching material.
I find that Smith & Wesson's centennial frame DAO revolvers allow me to get a higher grip so my hand is closer to the bore axis. This provides more control and reduces muzzle flip over the conventional DA / SA design.
Both Models are .357 Magnums but for anti-personnel purposes, I use 158 grain JHP .38 Specials. I carry Magnum reloads for the 640 in a moon clip in my vest pocket when around the property if I expect that my neighbor Mr Bear or his friend Mr. Piggy is out & about, otherwise, it gets Buffalo Bore hard cast 158 grain Keith style SWC "Outdoorsman" heavy 38 Specials. Magnums are BB or Grizzly 180 grain cast RNFP-GC. Hand full in the 640, but rubber grips make them doable.
Top revolver: Light weight M&P 340 for year-round dress-up town wear.
Bottom revolver: Performance Center 640-1 Pro Series for daily wear (occasional trips to town, and around the property) during spring / summer months. This one is cut for moonclips.
Both of these revolvers have tritium night sights, so I can see'em in low light.