There are no Fokkers yet. (
)
It's got balance issues and the refund service upon a change is a bit meh. The grind is very slow even in comparison to World of Tanks. Another thing is that they don't give equal weight to all nation trees, meaning the Russians and Germans have a significant hangar choice advantage over the others for now. The tiering is also still pretty beta, for instance, they put Lancaster bombers up against jet fighters. Not exactly a fair fight.
In fact, you'll find that though everything can down everything else in principle, there are nations with significant drawbacks to their units since the other nations have climbrate, weaponry, speed and other advantages at the same tier level due to their historical attributes not being compensated by hitpoints or so (especially pilots getting shot or wings, ailerons or tail controls if not the entire tail breaking off in the first cannon volley of a Russian who-ever-heard-of-it?-fighter can be a real pain).