I make no bones about it, I love smallbore (20 and 28ga.) shotguns.
This sums it up pretty good as I see it and Brister's book is one that should be read by anyone who likes scatterguns.
"There are shooters who definitely can put more birds into the sack with a lightweight 20 or 28 gauge than they can with a heavier 12. But this not due to gauge but to balance, weight, gun fit, recoil, speed of swing – or maybe how much the man likes his gun."
“Shotgunning – The Art and the Science” by Bob Brister.