humble,
I'd hold off judgment until it gets fixed, but based on what Pyro has said it should be clearly inferior to the N1K2-J, F6F-5 and all other 1943+ American fighters.
I really don't understand why HTC used the numbers off of the first prototype for the Ki-84. Essentially, if this flight model is accurate, the Ki-84 had a absolutely monstously overblown reputaion and the whole "Forget about it, it's a Frank." stuff was baloney.
I just can't understand how the N1K2-J is as fast despite having a less powerful engine and being less streamlined.
The perfromance is well below my lowest expectations, which would have been about 340mph at SL and 392mph at best altitude.