This the same Blakeslee that was supposedly quoting as dissing the P-51 in the other post?
As for the P-38 it was a far more effective fighter in general, than the P-40 or the P-39, the performance stats and FG records clearly show that. There is a reason it flew with the 8th and 9th AF and neither the P-40 nor P-39 ever did.
Fine manuever vs the P-47 (Buhligen) assuming you see it in time, otherwise your ashes, which is how most combats were fought, quick and over within a few minutes, or seconds:
The Corsair downed more than its share of Ki-84s and N1K2s in WW2, so I dont see why a less manueverable Fw190 would be such a tough nut? What makes the P-47D say, be able to shoot one down but not a Corsair?
WW2 air combat was not about 1 vs 1 duels. It was about ambush and killing quickly, using team tactics and the advantage of position, most times. Flying a fighter with high performance was by no means a guarantee of never being bounced, or hit by an opposing fighter you didnt see untill it was too late, which is the kind of circumstance that felled most of those who were shot down. Evasive manuevers only work if you saw him in time
Anecdotal quotes are interesting, but they say very little about the daily realities of the campaigns average airmen fought in, and too many people quote top aces (on both sides) as hard "proof" of something.
As for the original question, I agree, there is no question both the F6F and the Corsair in particular, would have been better fighters than the P-40 or the P-39, as they were in the Pacific. How much better I guess we will never know.