As far as store-bought range ammo goes, 44 special, 45acp, and 45 colt all feel about the same to me.
I have Charter Arms revolvers in 44 special and 45acp. I bought them both used. The 44 had been shot a fair amount and I've never had a problem, other than you have to watch the screws for loosening (I finally used blue Loctite). The 45acp had barely been shot. Apparently someone bought it new, discovered it had a problem, and traded it to the LGS without disclosure. I don't even remember what the problem was, but the factory fixed it for me quickly and for free, so that was cool. It hasn't given me any trouble since.
They're not only small for their caliber, they're light. That makes them very carryable. I carry my 44 often. The trigger has an odd feel to it, but it's not heavy. The fixed sights are fine. The factory grips are fine. The recoil is noticeable, but not sharp. I can shoot them about as accurately as most snubbies, which is plenty good enough for SD. The fat bullets are comforting to carry.
Are they a tiny bit smaller than a K-frame, or does it just seem like it? They're more lightly built, that's for sure. My Rossi 720 is a smilarly-sized five shot 44 special, but it's built thicker like a Smith K-frame. It's faster and friendlier to shoot, but I would need a thick belt to carry it. My Charter Arms will fit in a large pocket and not even sag that bad.
I shoot a few cylinders of light range ammo through them every once in a while, just for fun and to make sure they're in good shooting order. I have N-frames in the same calibers that I can shoot thousands of rounds through if I want to shoot a bunch of big bullets. And I have practice snubbies in 22lr and 38 special if I want to work on snubby basics. I figure the Charters will last longer than I will, if I don't overwork them.
This is the 45acp model. It has cool little spring thingies to hold the ammo in the cylinders.