1943/1944 planes should be perked low... like between 4 and 12 points.
Of course, other planes like the SpitXIV, Tempest, 109K-4(if it's added), Ta-152, Me-262, P-47M/N, P51H(did it even see combat?) and other planes of that nature- ones that can easily dominate the arena should be perked high.
Why? Keep it out of the hands of experienced players and keep them rare.
Imagine if the currently perked high planes were perked in the 8-12 perk range. "I'm going to take up a 205 today...." After 7 minutes of climbing, to your surprise virtually every con in the sky is a Spit.... not a SpitV, Spit I, Seafire II, or SpitIX... nope... it's got the dreaded Spit14 icon on it. And what's this? All the other cons are Tempests, F4U-4s and Ta-152s with the occasional 262 pilot.
Sweet, now that's what I talk about a fun arena. Hey, you wanna learn the aircraft before you pay for it Hazed.. try H2H or the TA. The MA has a price on it, otherwise what's the point of having the perk system in the first place?
Verm, MG151/15s were in 109F-2s. 109F-4 was the first model to incorporate the MG151/20.
Hajo, you are using incorrect data. The G10 in AH is not modelled after that G10 you have there....

Maybe you guys should try comparing the in-game G-10 to the K-4 data you have.
-SW