It's interesting to hear folks speaking of going to smaller bores as they get older. As a kid growing up in Texas, all I ever shot was a 20 gauge pump and a 410 bolt action. I didn't know anyone with a 12 gauge - those were for old men who needed more pellets (along with automatics). We mostly shot pheasant, dove and pigeons. A 12 bore was viewed as over kill, and back then 20 gauge shells WERE cheaper - as a kid working for every dime, I bought the cheapest thing out there. 20 bore was just viewed as the most versatile gun - could be used for small and large birds.
Now as an adult, I've begun to collect a large number of 12 bores - SxS's and O/U's. I love how they handle and shoot, but I'm always on the look out for a good small bore. There's just something about them that I like - maybe because that's what I used as a kid.