Since 1970, I've been shooting an AYA sxs Matador II, imp&mod, 20ga.
ALWAYS with 2 and 3/4 inch shells, unless I'm jump shooting ducks along the crik.
Most of my shots are under 30 yards, I'd guess, but the average overall range might be 20-40 yards. Years ago,I used to shoot trap load 7&1/2, but have graduated to 6s and 5s in recent years.
Find what works for you, but I've never needed the bigger shells.
Best wishes.