I bought the wife a SA20 compact a couple of years ago. I had it drilled & tapped to mount a Vortex Venom. Also had Kick-Eze recoil pad installed. It's a great little gun and have been thinking of getting one for myself. I can't remember which choke she is using. It's either a Carlson .570 or Hevi-13(.573?) She is shooting 3" LongBeard 6's. She is not very experienced with shooting so I wanted a more open pattern for her at closer ranges. At 15yds. she has about a vollyball size pattern and at 35yds. it's a solid, even pattern. At 37yds it's starting to get a little thin, but it would still kill a bird.
The only issues are it doesn't like to eject light trap loads, but it only has about 3 boxes of shells through it. It has gotten better the more it has been shot.