For strictly self defense purposes, the choice of gun is not nearly as important as knowing how to use it, at a moments notice, and with effectiveness.
Which ever one you choose, learn how to use it so that it becomes second nature.
Know where every control is and practice reloads.
And practice every thing else, too, until conscious thought is not required for its deployment.
They are all good ones for the intended purpose.
Just make sure it has no problems with the ammo you want to use.
Look for action shotgun type matches in your area to attend, too.
They will really help sharpen up your skills.
Walt Kelly, alias Pogo, sez:
“Don't take life so serious, son, it ain't nohow permanent.”