If we are discussing on the deck speeds (I haven't looked at the film), the F4U should be very close if not actually faster than the G10. Its suppose to be.
Fuel load is critical at low levels, when determining which is faster and which catchs which in acceleration.
The G10 is in its "sweet spot" between 10k-20k, and its in that range where its the fastest plane in AH.
Above that or below that, it usually falls into the 2nd to 4th range.
Another example is the P51D and the Yak-9U. The P-51D is faster than the Yak right? I mean 437mph compared to 417mph?
The answer is maybe.
If the P-51 has WEP left its faster at almost all altitudes, except for a very narrow band at around 7,000ft (which is what I dive too if I think I'm being chased by a P-51 while in a Yak.)
If it doesn't have WEP left, there are additional areas where the Yak is superior, and the differential is much lower at all altitudes under 20k.
Enough rambling

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Vermillion
**MOL**, Men of Leisure