S!
Some of the Soviet aircraft are overrated.
The Lavochkins and Migs all have better performance than even my Russian data would indicate. It seems Oleg has used the test data for the prototypes, instead of tests for a factory produced model. Because of poor Soviet manufacturing standards, the difference was often in the area of 15-20mph in speed and 15% in climbrate. In IL-2 the Lagg-3 is particularly overrated. The La-5FN is also too fast and climbs too well. The Mig-3 is far more maneuverable than historical data would suggest.
The Yaks don`t seem to be out of balance. I think this is because for some reason Oleg has a personal dislike for Yakolev, the designer of these planes. If you have been following discussions on the various boards for the past couple years, you would remember him dissing Yakolev at every opportunity, while simultaneously praising Lavochkin. These two had a personal vendetta during the war and Oleg seems to have taken the side of Lavochkin...
The German aircraft seem to be well done with perhaps the exception of the 190`s which seem to lose control input at high speeds too easily.