A 12 ga, 1 oz. slug has a lot of stopping power, but there are drawbacks, to going with shotgun shells.
Let's take the Mossberg 590M for example. It's a semiauto, which would give good firing speed; if you were being stampeded by 50 man eaters; but the mags only hold 20 rounds max. That means you would have to reload twice to get at least one shot in every pig; but that 20 round mag would add considerable weight to the gun. This would make it more difficult to swing the gun back and forth, to hit the most imminent threats.
Aside from that, you have to carry the weight of those extra mags with you; as you go strolling in the Texas night.
Certainly the stopping power of the 12 ga, 1 oz, is an advantage; but that tradeoff might not be advantageous to someone who is less muscular.
I've seen women hurt themselves with the recoil of 12 ga shotguns.