And there are 2 different versions of the Shiden... The Kawanishi N1K1-J and the 2-J...
The -1J had major problems with the landing gear, and the limited visibilty on the ground problem.... Only 1,032 -1J's were produced, starting in 1943...
The F4U-1 series began production in June 1941, and the F4U-1D in April 1944... The F4U-4 began at the end of 1944... The horsepower went from 2,250 in the 1-D, to 2,485 hp in the -4... Not bad...
The only thing the N1K1-2 J retained from the -1J was the engine, the wing, and the armament of its predecessor, with productions starting in June 1944...
The fuselage and tail fins had been completely redesigned in order to allow the wing to be lowered from the middle of the fuselage farther down... This of couse made it possible to shorten and simplify the landing gear and consequently to improve overall visability on the ground...
A huge production run began in June 1944, but due to the continuous raids by American bombers, only 423 M1K2-J's came off the factory lines before the bombs were dropped and ended the war...
And like many other aircraft in the PTO, Many of the 2-J's were sacrificed in suicide attacks...
I believe the that the -1J would have had serious issues with a decent F4U1-D pilot with 3-8 kills under his belt, let alone one flying in a -4...
The -2J would have stood a much better chance of combattin the -1D, but were seriously in a bad situation against the F4U-4 (both with skilled pilots)...