A million dollar question
The single-most important feature for the late-war fighters was that engine has plenty of power at all altitudes, that incorporating the 2-stage supercharging of either 'flavor' (including turbosupercharging). Laminar-flow wing was good, but there was plenty of fighters that were well above 400 mph that were without the laminar-flow wing.
Granted, a low-drag wing and power surplus are bound to create an over-performer.