I always pack a spare magazine, a backup, a spare magazine for my backup, and a knife.

If I can't adequately defend myself with that much, then no amount of extra ammo would make a difference.

That being said, I think that like so many other choices regarding self-defense, that the matter is highly subjective, and that there is no such thing as an ideal, universal loadout which will work for everyone, ergo choices in regards to self-defense are best left to individual discretion.

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Shooting Comfort is bilateral.