The N1K2-Ja had surprisingly good maneuverability due to a mercury
switch that automatically extended the flaps during turns. These
"combat" flaps created more lift, thereby allowing tighter
turns.
Kawanishi
N1K2-Ja
Shiden Kai (George)
The N1K2-Ja was the best fighter used in significant
numbers by the Japanese Navy during WWII. The Japanese developed
the Shiden Kai to counter high-flying
B-29s.
You can see this aircraft unsergoing restoration in the Restoration Projects section of this site.