Your choice can be based on performance as well as effectiveness. If you chose other, please tell us which aircraft and why.
Make sure you voteFor bomber I picked the SM 79 for its versatility and length of service.
For a fighter I would probably pick the M.C. 205. As far as I know it has the best war record out of the 3 choices.
I honestly don't know much about the service of the other 2 fighters.