I think one of the biggest mistakes S&W ever made was moving to the J-magnum frame. .357 in a J-frame was always more of a marketing gimmick than a customer demand, yet the larger frame affects comfort and concealability.
I don't find that to be true.
First, .357 Magnum in a Model 60, with its steel frame and 2.125" shrouded barrel is not horrible to shoot given a proper grip.
Now, to be fair, I practice with .38 Specials and I carry .38 +P, but that's due to a) my habit of shooting it on a regular basis for proficiency and the resulting wear and tear on the revolver with a steady or even frequent diet of .357 magnum, and b) the adequacy of .38 Special +P loads in a 2.125" Model 60, and improved speed and rapid fire accuracy with +P loads as opposed to .357 loads.
I get velocities around 675 fps with 158 gr .38 Special, 950 fps with 125 gr .38 +P and 1065 fps with 158 gr .357 Magnum. The .357 Mag is just not efficient in a 2" barrel, while the +P load is both a significant improvement over the standard pressure load, and potent enough to do the job and is still pleasant to shoot.
Second, the J-Magnum frame is about 1/8" longer to accommodate a 1/8" longer cylinder. There is more metal around the hammer, but way less than with a hammerless or shrouded hammer style J-Frame.
First, let's compare a Model 36 no dash with a Model 36-10 with the same 1 7/8" tapered barrel on a J-Magnum frame. It has a slightly longer frame to accommodate a lightly longer cylinder (about 1/8") and a slightly longer radius in the frame from the back of the top strap to the top of the grip, resulting in a little more metal around the hammer:
Then let's compare the same Model 36 no dash with a Model 60-14 with J-Magnum frame and 2.125" untapered barrel with shrouded ejector rod. The frame and cylinder differences are identical, with the major difference being the 1/4" longer barrel.
Then, let's see all three side by side.
Even with the longer barrel and larger frame the Model 60-14 fits in the same holster as the Model 36 no dash and is just as comfortable for IWB carry.
It is however much more durable and will handle .38 +P loads without complaint, while the Model 36 no dash is a standard pressure .38 revolver only.