ENY isn't the best way to gauge power or easy mode status. Per ENY, the P-51D is easier than the Spitfire Mk VIII, and its stats would support that claim too, but a lot of people in this thread would instinctively disagree with that.
As one American who switched from Spit VIIIs to P-51s put it, roughly "The P-51 won't do what the Spitfire with do, but it will do it over Berlin."