I'll never shoot a pump at ducks again. That being said they definitely are tried and true. If you go the pump route take a look at the Remington 870. Semi-auto there's a lot of good options out there but my last two have been Stoeger M2000s. Go with a longer barrel, it helps swinging it and also keeps it safer in the blind/pit. I see no need for 3.5" shells, but some guys swear by them. 3" have always worked out great for me.