Heya Widewing,
There is great test data available on the A6M2 and A6M5 vrs P-39, P-40, P-51A, P-38F, F6F-5, F4U-1 and F4U-1D in "Warbird History F4U Corsair" by Veronico and Campbell.
The results are interesting indeed on just how competitive the early A6M2 really was with the P-39, P-40, P-51A and P-38F.
Later
F4UDOA