Effectively from researching this type, this aircraft was in essence the Jap version of the Ta-152 and Fw-190D series. As strange as it may sound and yes granted desperation for development of fighters was made by the Axis in 1945 and this aircraft will remain a ''what if'' project if she was against Mustangs and late Thunderbolts, from what I understand that the cannon arrangement on the 87' was similar to the Fw-190D-11 in layout.
I'm not going to lie but the question begs of how effective also it would have been against a B-29 Superfortress which was it's intended role as a bomber killer, granted we'll never find out but we can surely see what the outcome is when this is a fully fledged bird in our simulator.
This plane in my opinion is similar to the Mitsi A7M Reppu.. a good design, but never proven.
BlackAce