I have done some recent research on each of these four aircraft and the way some perform in AH has, at least to me, come under question. This is due to the numbers and facts, as well as pilot opinions. First off is the wing loadings of each aircraft:
Spitfire(early versions):27Lbs per sq-ft
P-51D:39Lbs per sq-ft
Bf-109:40Lbs per sq-ft
Fw-190:48Lbs per sq-ft
Other factors include center of gravity, which is another critical factor in maneuverability. The further forward the better the stability,but lower the maneuverability,and vice verse.
Spitfire:at least when the fuel tanks are full,it is tail heavy,especially in earlier versions
P-51:due to the placement of the fuel tank,and radio,as well as indicating flight characteristics,show it is tail heavy
Bf 109:is a forgiving fighter and as far as i know no heavy equipment was behind the pilot,it is also light and had a big meaty engine hung ont the front.This suggests in level flight it may have been nose heavy.
Fw190D:According to the information i have found,the 190 was a little unstable and had a fuel tank in the rear,suggesting it may have been tail heavy.
If the pilot accounts i have heard are true, in a dogfight from best to worst are:
#1:spitfire
#2:P-51
#3:190
#4:109
Of course the 190 vs 109 is controversial, as the 109 was probably better at low speeds,especially early versions.
Now for my list,at high speeds or speeds above 300mph I would vote:
#1;P-51 and 190 as they were easier on the pilot.
#2:spitfire only because the controls seemed slightly slower at these speeds.
#3:Bf 109 as its controls were very difficult at high speeds.
At low speeds the spitfire comes up on top followed by the P-51,109, and last is the 190.Of course earlier 109s were lighter and probably could beat a Mustang at low speeds.
The bottom line is that the modeling on each aircraft is questionable,except perhaps the pony as AHes creator flew it,and this is also confirmed by a earlier post.HTC may also want to look into other aircraft as well as their modeling is also questionable,but i haven't done enough research to confirm this.So at least for now spitfire pilots rejoice.
-WING47