Six to one, half a dozen to the other ...
I've carried a 3" J-frame. I carried it mostly as a belt gun. In that particular instance I achieved similar accuracy with that 3" revolver as with my issued 4" revolver when qualifying with it on our 1-25 yard qualification course of fire at the time.
My older 649 made for a better 'pocket carry' revolver than the 3" J-frame, though.
I originally wanted one of the 3+" SP-101's, but had to settle for a DAO 2.25" model because of availability. I don't regret the choice. It's been a fine revolver. I originally tried occasionally carrying it as a 'pocket' revolver (w/holster) when I wore an insulated vest in cooler weather. It was still a bit too heavy for my tastes. It became mostly a belt gun back then. As such, I'd prefer it had the 3+" barrel, given my druthers. I sort of look at it from the perspective that if I'm going to carry it as a belt gun, I might as well have the slightly longer barrel for the slight advantage it offers
my eyes.
I think if I were going to limit myself to only a heavier, short-barreled, small-frame Magnum-capable revolver, I'd choose the 3" model. DAO versus traditional DA doesn't really matter
to me when it comes to a dedicated off-duty defensive revolver, but then I've spent a fair number of years acquiring revolver skills and practicing them. Other folks might easily feel otherwise.
I won't willingly part with my 2.25" SP-101 ... I just don't find it filling a role as a frequently carried off-duty weapon because my Airweights better fill that role, especially for 'pocket-carry' use, as well as a couple of other carry methods.
I think the improvements offered in the medium-bore (.38 Spl/.357 Mag) defensive ammunition in recent years has blurred the lines a bit when it comes to 'performance', in some instances, but that's only a personal opinion influenced by my needs.
If I desired to maximize the potential performance of a .357 Magnum revolver carried for defensive use, I'd go back to carrying a 4+" 'full-size' revolver ... which for me means 4-5" ...
However, the shorter-barreled models, combined with much of the quality defensive ammunition being produced nowadays, still serves
my anticipated, perceived needs well enough ...
I suppose it really depends on how you feel about
your revolver as you spend more range time with it.
A longer sight radius is preferred by some folks ... but then the approx 1" difference you're talking about might not be much of an issue for many folks.