I'd go with the Beretta 21 and buy as many different types and brands of ammo that I could find. Field test all of them and find the one that works the best in your gun; every .22 that I've owned has been somewhat particular as to what ammo it likes and what it doesn't like. Then practice with that ammo until your confident with it under every situation, i.e., FTF, FTE, misfire, etc. One thing that I have found to be relatively true in regards to small .22 autos is that the smaller you go in gun size, the more critical internal tolerances and functionality become. It's not always possible to simply shrink a gun down and expect everything to work the same way it would on a full size model.