I was confronted with this question recently, and made the choice for a S&W 586 L-Comp, a 357 magnum, 7 shot, revolver with a 3 inch barrel.
For situations where I open carry in the forest, I carry a 44 Magnum single action in a belt holster. For the situation that confronts me every day in the city, I have determined that the choice of open carry is undesirable for my circumstances.
For every day carry, I have a S&W 22-4 which I carry AIWB. It is big, but pretty concealable in this mode. Uses moon clips for a pretty quick reload, should that be necessary. I have confidence in this choice, and consider the 45 ACP cartridge to be the rough equivalent of 44 Special if one were to make such a comparison.
My decision to put the 7 shot 357 magnum into the rotation took into account the effectiveness of the cartridge, the simplicity of the manual of arms of the revolver, and the additional shot should it be necessary. I do not feel under armed with the 45 ACP, but I am old enough to remember the "one shot stop" statistics concerning the 357 magnum, which, with the addition of another shot before a reload, tilted the scales in that direction. The smaller profile of the 586, with a round butt and a shorter barrel tends to make it a little more concealable, and given my body build opens the possibility of using a pancake holster OWB and a jacket.
I think the 44 Special is a dandy cartridge, but in the situation of a revolver I have become fond of the moon clip as a means of keeping reloads well organized and easily put into use. As far as I know, I am unaware of a 44 Special revolver with the feature of moon clips. -So I guess factors extraneous to the initial question were as important in my decision than simply the chambering of the revolver.
As Gus McRae said in Lonesome Dove, "I don't want to be killed for lack of shooting back."