Well here's my .02 cents, buy one. Whatever you find that fits your budget and local availability now. stay away from airweights if your gonna fire full-tilt rounds often. ( I had a airweight .44 mag and it was tough on the hands with heavy loads.) With the wide variety of ammo choices either would fit what you would be doing with it. I've owned many handguns of multiple varieties of calibers, either one of these will serve you well. If your not gonna handload the .38-.357 should be cheaper to shoot but in this day and age of the panic fueled market place all bets of that are off.
It all boils down to this, the best gun is the one that you own. If you don't have one you can't use it.