Keep in mind that flying habits also affect what is the best fighter for somebody.
Spitfires are my favorite aircraft, but for me the F4Us and Ki-84 are much easier to use. Luckily I like the Ki-84 too.
As to durability, so far as I can tell it is more durable than any Spitfire in AH. The only real shortcomings it has is high speed handling, which isn't that bad, and gun ballistics. I can do things in the Ki-84 that I cannot in the Spitfire and I feel like I have the advantage on any Spitfire in AH at normal combat altitudes. Don't fight a Mk IX or Mk XIV at 25,000ft though, that would be dumb.
Contrary to what Benny Moore said, the Ki-84 handles anltitude gains about the same as the Mk XVI. The Mk XVI's clipped wings and Merlin 266 cause it to lose effectiveness over 15,000ft as well.
I have never shed the control surfaces on the Ki-84 due to overspeeding either. Just watch your speed and be willing to let things go if you have too, which isn't very often. Usually all that dive does is blow their E and place me above them. Now the Mossie, that is a control surface shedder.
Basically, there is nothing in AH that I feel completely outmatched by when I am flying a Ki-84. I cannot say the same of the Spitfires.