16ga is popular in some south america countries, and seen in Europe from time to time in shotguns, drillings and doublerifle drilings.

There has been a regained interest in UK for a few years. I would any day of the week choose 16 ga over a 20ga. I shoot 12ga at moment but use 28-32 gram loads, shotsize 2,6-3mm for just about everything.

A browning B25, Piotti, F.lli. Rizzini or Perazzi in 16ga would be simply gobsmacking.

I would say 15 is perfect for quail, prairie hens, snipes, partridge, pheasants, pigeons, rabbits and hares.

20ga is nice but its not suiteable for loads over 28grams and best at 23-26grams in my opinion.

Squareshot theory is intetresting.

10ga is a great wildfowling on the shores or marshlands. There should be more guns made in 16ga and 10ga.