I started off with a .38 Special Airweight Smith 642. Fun little gun, but emphasis on little. Kicks like a mule, and with .38 +P loads in it I'd swear I'm not even using the gun. Just gripping the rounds and squeezing the primers until they go off in my hand. I once tried to put a hundred round thru in succession. Make my hand and wrist sting.
Then I played with a .357 Smith 640. All steel gun, bit more mass, but still smallish, at least for me and my long fingers. 110 Magnums aren't bad to shoot thru it, and the performance whether one likes gelatin or statistics is darned good. Full power 125s and 158s are close to unmanageable, but it makes a helluva racket on an indoor range and scares everyone good. For giggles I like to occasionally bang some 180 grain loads thru it. People around me just stop shooting.
These days, and for the past 7+ years, I've been carrying a Glock 23. I'm 6-1 and 190, I wear untucked shirts, and I carry IWB. Unless someone comes up and hugs me, they don't know I'm carrying.
I've been toying with the idea of a Kahr P40. Little thinner, but I still haven't made the leap.
None of this much matters though because what works for me may not work for you, and vice versa.