In real life, my three favorite planes (no no particular order) are the Fw 190, F4U, and the Typhoon.
For me there's something special about the development of an aircraft that when first flown has major issues, but then is refined into an excellent design. Each of these planes had significant design issues that had to be addressed before they went on to become stellar aircraft.
In game, I've never been able to settle on one particular favorite, I like them all.