For me its the P-51s, I remember being at an airshow when I was 10 (now 27) and a flight of 51s came screaming by, the sound of the Merlin still echos through my head and gives me goosebumps. Being in an engineering career, the inovation and speedy design time also appeals to my mechanical nature.
As for flying it in AH, it fits me very well, I enjoy the speed, the gun package, and the multiple radiator and oil leaks.