The argument against 20 gauge in a defensive shotgun has been the 1301 is lighter, recoils less, is better featured than 20 gauge shotguns, and launches Flite Control buck.
Seeing that Federal is releasing 20 gauge Flite Control, it makes me wonder why no 1301 in 20 gauge. It could be handier, recoil less than the 12, while still delivering effective buck loads. Plus, the Brenneke 20 gauge slugs are available.