The Ki-100 has always baffled me. It is usually reported on with glowing praise, yet on paper, seems to have 1941 era Spitfire Mk.V performance.
" A well-handled Ki-100 was able to outmanoeuvre any American fighter, including the P-51D Mustangs and Republic P-47N Thunderbolts which escorted the B-29s over Japan, and was comparable in speed, especially at medium altitudes"
" The Ki-100 along with the Army's Nakajima Ki-84 and the Navy's Kawanishi N1K-J were equal to the latest Allied types in the final year of the Pacific War."
Not sure how that would be possible, considering the "latest allied types in the final year of the Pacific war" would be P-47N's, P-51D's, F4U-4 and a smattering of Spitfire MK.XIV's all of which would have enjoyed a 80 mph speed advantage
It was not possible. But, sometimes the authors give themselves too much of elbow room to try and bend the facts and figures, as well as try to wrap the stuff in shiny paper in order for their story or book sells better.
Many times it is better to translate the Japanese Wikipedia article on the Japanese stuff (as well as German-language Wiki for German stuff; same with Russian for Soviet stuff), than to go with usual English-language Wikipedia as a source.