I had three occasions where there were three USN planes against my lone Zeke - me on the deck, they booming and zooming (first time 2 F4Us and a Hellcat, second 2 Hellcats and an F4U, third three Hellcats). First time they managed to empty their ammo and score a couple of fuel hits while I downed one of the F4Us and RTB'd. Second, I got an F4U again, third, they got me but at the cost of two of them.
Currently I'm 23 and 10 in the Zeke.
11 kills of the F6F-5 and 7 kills of the F4U. 2 F4F-4s. 1 TBM. 1P-40E. 2 LVTA2s.
Of course ... all 10 deaths were from F6F-5s.
The A6M5 is fine. You just have to let them outnumber you so they'll engage.