Psst.
The 4-hog completely owns the k4 at any alt, in every single aspect, except the climb rate where the k4 wins, with a small margin. Something simmilar with tha La7 too.
This is true, I'm not good in the Dash4 as this is the first tour i've gotten around to flying it, but had a few duels against a decent K4 stick and it has a number of surprising tricks to play, and won every time.
like a spitfire you can make quite a few mistakes and recover quite easily, the whole gear's dropping at 400mph I find quite funny since you can pull off a number of tricks and be inside a K4 or spitfires turn radius in no time using flaps.
Dash 4 is the only F4u thats able to play in the vertical game due to its climb rate which makes it all the more deadlier.
As for speed:
With Wep the K4/Dora/La7 are faster under 9k, they even outclimb it to 9k, however with full flaps only the La7 even comes near touching the Dash 4.
Max speed on the deck, only the K4 is slower by a small margin, acceleration wise only the La7 is faster - where Dash 4 is bout even with everything else.
It has all the great qualities of a late war monster, but considering it has very very few weaknesses this is why its a late war perk monster.