About the only things the P-38L has on the F4U-4 is ordinance load, (10 rockets vs. 8) high-speed roll, (but not significantly) stability at stall speeds (counter-rotating props eliminating torque) and placement of the gun package (debatable which has the superior armament with only the single 20mm and only 150 rounds, but both are more than adequate). The -4 is faster, accelerates quicker, is more maneuverable and has a higher sustained rate of climb, and I'd give the F4U the clear advantage in high-speed maneuverability (except rate of roll as mentioned before). I'm not sure on zoom as I've never tested it, but I've rarely had a P-38 catch or escape me in the vertical when I'm in a -4 from a near or co-E start (that being said, the -4 is generally capable of creating a starting advantage anyway).
The 38L more evenly matches with the 1A. The 1A is faster, but the 38 gains the advantage in rate of climb and acceleration.
