Sure, but no matter how powerful the air rifle, I wouldn’t want to have to rely on it if a murderous criminal or tyrant were coming after me.
A .45 @ 950 fps from an air gun is way more than enough. 950 fps is as fast as ammo coming out of a 1911.
No...but if you are running out .22 long, it is decent replacement. I bought a case of pellets—11,000 of them. I am not running out of them any time soon.