Kind of really getting interested in revolvers and giving some thought to options it occurred to me why not follow the example of @Mike Pipes and carry multiple J's vs a single 66. Weight wise its a wash, distribution of weight it seems like the J's win. Ammo capacity wise two J's win. Capability wise 357 short barrel vs 130-135 38 or wadcutters someone more knowledgeable than me will have to assess.
19 Carry Comp 34.2oz 6 shot
66 2.75" 33.5oz 6 shot
640 Pro 22.2oz 5 shot
642 Pro 14.6oz 5 shot
M&P 340 13.8oz 5 shot
340 PD 11.8oz 5 shot
I am looking at this from the standpoint of a civilian who is extremely unlikely to ever need a gun, not from a police or person who lives in a high risk area.
I am also assuming that all mentioned would have action work.
ETA A 66 + a J vs 3 J's