I'm reading a book on Japanese Aces now, and the one big complaint is that the  rides are all hideously undergunned.  Ki-44s weren't cannon equipped for the most part (either 2 x 7.7mm + 2 x 12.7mm or 4 x 12.7mm were the most common variants).  
Stick with the Zero, or the Ki-84 if you like the Japanese rides (I do) - unless and until we see the Ki-100, or the 37mm equipped Ki-45 bomber killers!
EagleDNY
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