I've had both, the .22 is the one I kept. .177's work fine for broadside and head shots, but the .22 will penetrate the vitals at most any angle.
I use 21g Beeman Kodiaks @600-700fps, these are domed conicals. The weight of these pellets allow pass through penetration on frontal shots, and have taken grey squirrel at 65yds. Shot a raccoon out of a tree, and one ground hog through the heart @ 35yds with the same set-up.
I wouldn't try that with my old .177