Lets see... I don't fly a huge amount and I usually spend most of my time hunting, and GV pounding while avoiding horde flying. Last tour I had best K/D in the following:
P-40N: 21:1 
P-39Q: 15:1 
Yak-9T: 10.5:1 )
F6F-5: 16:1 
Spit 8: 8:1 
N1K2-J: 12:1 (tied for first)
Ki-84: 16:1 
M3: 3:1 (tied for first)