I have an old, old Stevens bolt action 20 ga that I refinished when I was 11. Stock, trigger, blued the barrel. Cut it down and put rifle sights on it. I still love to shoot that gun. Very straight shooter.
Of the ones I have shot so far, nothing is like my browning citori ultra sporter. Most of the guys I shoot with have perazzis and krieghoffs, which seem amazing.
I havd two Berreta A303's one in 12 and one in 20...I love them both but the 20 is by far my favorite...both with English stocks....you can carry and shoot the 20 all day with no effort
If I had to keep 1 gun, it would have to be my 1st shotgun. Ithaca SKB model 100 20ga SXS shotgun. It has harvested truck loads of rabbits, quail, pheaant,a few ducks, squirrel, fox, pop cans, clays, and a few cats. Very well made gun. I like it so well that I bought the O/U version.
Ithaca featherlite 12ga was fun to shoot. My buddy let me use it last year during gun season and took a fat doe with it. Also dig on the remmy 870 but my favorite is the mossberg 500.