Valid question...
I'm a Glock guy, I carry a Glock 19 99.9% of the time so I considered the 26. My main criterion was the ability to carry in a pocket or on the ankle. Unfortunately I can't do with the 26 due to it's width and generally "blocky" shape. If I could have gotten away with a 26, I'd have bought one in a heartbeat.
The curves of a revolver help break up the outline when carried in the pocket and also help smooth out the draw. There's also the fact that it can be fired
through a jacket pocket if necessary (without malfunctioning). This ability allows it to function not only as a BUG, but as a "preemptive" type weapon since you can have a firing grip while still concealed in the pocket.
As far as other small autos. I'm just not convinced as to their reliability. It seems that the smaller the auto, the more finicky it is and the more likely you are to just get one of the many "lemons" that just don't work and never will. Kahrs, Kel-tecs, etc. are all plagued by this phenomenon. If you step up to the upper end of the small auto range (e.g. PPK etc.) you're back to a gun that's not only as large or larger than the revolver (length and height), but also heavier.
Basically, you trade reliability for concealability...not something I'm comfortable with.
That looks a good bit smaller than a Glock 26...
S&W 442: Length-6.37" Width: 1.18" Height: 4.25 Weight (empty) 15oz.
Glock 26: Length-6.29" Width: 1.18" Height: 4.17" Weight (empty) 19.75 oz.
While the numbers would indicate that they're pretty close, there is definitely a difference in the way they actually carry. For example, while the revolver is the same width, the only part that's actually that wide is the cylinder. The rest varies which makes a big difference in how it hides.