The U.S. 1.1-inch gun versus Japan's 25 mm anti-aircraft gun

How did the U.S. Navy's 1.1-inch anti-aircraft gun compare with the Japanese 25 mm gun?

The preference is for the Japanese 25 mm because of its firing rate and more varied mounts. Its usefulness is disputed, with one response defending it as a flawed but serviceable point-defence weapon.

The Japanese 25 mm is preferred to the American 1.1-inch gun on rate of fire and mounting flexibility. Both are criticized for box-magazine limitations, while the American weapon is tied to its quadruple Chicago Piano mounting. Single, twin and triple Japanese mounts provide more installation options. Their actual defensive usefulness produces disagreement: a dismissive joke calls the 25 mm merely decorative, and another contributor objects that it remained a serviceable point-defence gun despite its flaws.