In the 4yrs I've been flying AH, I have flown A20 more than any other... The main limiting factor on A20 is the old prewar airframe.. It wants to go faster than the airframe will tolerate, if you do, things break and it starts shedding parts.. Thats why Douglas took all their wartime experience with A20, and all its upgrades.. And poured it into a new plane, the A26.. It won't shed parts like A20!
And it will have WAY higher dive speeds, will sustain them longer with its slicker airframe.. This will make it far easier to zip in to a target quick, far harder to catch them, and far more survivable all around.. Late war fighter guys don't like that idea..
RC