After shooting 38's it takes too much work to get the .357 chambers as clean as I want them.What Greg said is true, but I wouldn't really worry about it. Make sure you scrub the cylinder chambers after you shoot though.
The difference in power between the .357 and .38 spl is almost like comparing the 9mm and .380. The .357 is about twice as powerful as the 38. And if you shoot them side by side, you can tell! Especially out of a small framed revolver.
With that said, .357 magnum is my favorite cartridge and I would highly recommend it!
Some may not know, but S&W made the L frame because the K frame will not stand up to a heavy diet of .357 magnum. I have a .357 and because I hand load I am able to load lighter charges in the .357 cases.I'm not a fan of recoil so I don't have a .357. That said, if I were to devote resources to a dedicated house gun for my nightstand, it would be a full size .357 like the GP100 or a K frame Smith. It's probably the best defense round there is.
Even the Model 10 had/has folks who claim it will shoot loose on a diet of .38+p. Just looking at them side-by-side, the 10 seems no flimsier than the LCR .357. I realize that looks ain't the whole story, but still...I think the Classic K frame is the Model 10. At least that's the one I think of. Plenty strong for the 38 special. I was never a fan of the Model 19, I preferred the Model 27 based on the N frame. Mine was the Model 28 Highway Patrolman.