G A is right. There is no way to say definately that Brand A, # ? shot will pattern well. Each gun is a law onto itself. Plan to get a couple of choke tubes of different constrictions, buy several boxes of different brand and shot size ammo and do some shooting.
That said, there are some constants: Just because it takes 3.5 in. shells, doesn't mean it'll pattern best with 3.5" shells. Try 3" if tthey don't seem to work well. Larger shot size (#4) will generally shoot better in an open choke. Smaller shot (#6) will shoot better through a tighter choke.
I think if you do a search of topics on the board, you'll find that Winchester Supremes either the lead or their version of Hevi-shot, shoot well in a wide variety of guns and chokes.
If you plan to go to Hevi-shot, you'll need a more open choke. It's harder than lead, and generally doesn't do well in a tight choke.
I know this is not the information you were looking to get, but it is what is it. It's the process we all had to go through.