These planes were the schoolhouses of the allied air forces, and they should help you ensure your printer is ready to churn out the steady supply of war material needed for victory.
I recommend printing these free models to see how they go before purchasing other models. If these print successfully the other WW2 aircraft collections should be able to print just fine.
Models are created and intended to be printed in 1:285 scale, they should be printable larger, but likely won't work smaller than this. I printed them using a Prusa i3 Mk3. I recommend slicing with Cura and using tree supports. You'll likely get the best results using the .STLs of the planes that are sliced in half (labeled L or R in the folders). I'm finding that Cura 5.0.0 has trouble slicing thin wings, so I recommend Cura 4.9.0 instead.
Aircraft Included: