The war against Russia was succesful for Finland in many ways, they were also very good pilots, using out dated planes to beat the Russians in the sky. Brewster Buffalo and Mörkö Morane (Morane-Saulnier MS 406) against the IL-2's and Polikarpov I-15, even I-16 and the I-153 in the latter stages.
Rumours are also, that when one of the few I-185 prototypes (4 recorded produced in total) flew over Leningrad in thick snow clouds it strayed to Finnish air space and it was taken out by a Brewster Buffalo in '41, and that's supposed to be the reason the Polikarpov Design Bureau cancelled the project.
I'd say the Finns were quite formidable, in the air at least.