Actually it is very interesting reading if you go to the source - try to use google translate...
Several points:
I-16 vs Hurricane - Russian pilots clearly preferred I-16 for having much better acceleration, more reliable radial engine that worked with several cylinders damaged, had better ammo. It was quite on-par with 109E...
Later in the war they install Russian machine guns on Hurricanes as they were not satisfied with .303 cal MG.
P-40 - was flown very differently - they burned the engines and run them with different calibration to make the full use of P-40s. The engine was very gentle and requires very gentle handling of oil - general P-40 was underpowered.
The guns on wings were removed and only synchronized were used to improve the performance. P-40 moved to the supporting roles (attack)