I have been using a Benelli H&K SBE since the early 1990's. I've been killing geese and ducks all these years both in Michigan as well as Canada. I never found that 31/2 " shells kill any better than 3" for geese. I tried all kinds of steel as well as Hevi shot and bismuth and find that they all kill well for me. The last 5 years I bought a Benellli camo M2 and its my favorite now. I been using it with a Cremator MR range choke in it. I shoot the regular blue box Federal 3" #1 steel 1 1/4 oz. for geese and it kills big Canada honkers out to 40 + yards with no problems. They are very inexpensive compared to other brands. I shoot #3 and #2 for ducks and they work great with the same choke. I take about 70 geese and about 40 ducks (mallards and woodies) a year at my friend's small property with a pond. Just me and my dog. It's only 20 minutes from my house. It's great being retired now. Good luck to you.