I shot a .45 ACP Federal HST through several one-gallon milk jugs filled with water. Awesome blossom. That's what I carry now in all my guns. A stock G23 is my EDC although I have barrels for 9mm and 357 Sig for it.
I suspect that anything short of FMJ in a 357 Sig is going to be lethal if you can hit what you're aiming at.
I second the www.georgia-arms.com. They provide good quality reloaded ammo at a good price. www.ammunitiontogo.com also has some good deals on it at times. 124gr. vs. 147gr. is just a personal choice. To reload the round a lot of people actually use the 9mm bullet which is why a lot of it found is in those two weights. Which one you use really won't matter. The 147gr. will penetrate a little more and may carry a little more punch at longer range. For general use it won't matter which one you get.