My advice is to try all three size frames. The K,L and N. I have all three of them. Depending on the size of your hands this will help you choose the revolver that feel good to you and you can shoot well. While the N frame is the most comfortable shooting 357s if you have small hands you might have trouble with reaching the trigger. I do because I have very small hands. The L frame does have the same grip size as the K frame but with the full underlug the revolver tends to be muzzle heavy. I shoot the K frame magnum the best. But that does not mean its the best revolver. That depends on you. Again, try them all.
Regards,
Howard