Well, I have to admit I know nothing about the high alt performance since I rarely go over 3k AGL.
The LW planes also have some issues in this regard. I dont remember the details, but I vaugely remember one of the LW guys (maybe Wotan?) saying that the 109F-4 is either running too much boost, or its WEP time is two long for that boost or something to that effect. Crumpp has also said that the 190A-5 has some type of problem with its boost setting being too high or two long, cant remember which.
Its not exclusive to the Spit V, its just that the Spit V was so good already...
