Federal #3 7/8oz blue box or 1oz premium red box @ 1350 have both worked well for me in the 20ga. The Kent 7/8oz is OK also. I believe it is Winchester, has a 1-1/16oz Blindside load, I won't buy Blindside for myself, though. And of course there is Hevimetal 1oz if you can find any.
WW also have a 1oz in the Dryloks at 1350fps.
Any of those loads will kill ducks to some pretty impressive ranges out of my CZ. Killed a few snows & specks with it, too, over dekes, in da lips, not pass shooting.