What kills did the P-63 get? Unless I missed something, there's a few stories floating around about the P-63 maybe shooting down a Japanese fighter in the far East.
That's even less credible than the stories about the Maus being used; they, at least, remain consistent about what happened for the most part.
Actually your wrong, the P-63 is far more credible as its proven it was in combat and flew in combat strength. The Maus never seen combat. Period. End of story. The V1 (first Maus produced) had no gun and a wooden turret. The V2 was blown up by its crew after trying to evacuate and the tank broke down. It did not fire a shot, fact is the tank was blown apart from internally either from the crew detonating something inside or the fuel tanks. Either way it was not in combat.
What is sitting in the Russian Moscow Museum is a Maus tank (The body of the V1 and the Turret of the V2) (or the other way around?) either way it was pieced together for testing purposes by the Russians.
There are hundreds of myths behind the MAUS, the most credible thing I can actually find about it - that Hitler wanted to use the MAUS to plug holes in the Atlantic Wall because frankly the MAUS was nothing more then a stationary pillbox with big guns.
P-63 Seen combat, was in multiple squadron strength. If the luftwaffe bothered to put planes in the sky in 1945 then the P-63 would have a kill sheet, fact is however after Operation Bodenplatte the Luftwaffe virtually didn't exist. Operation Plunder and Operation Varsity are key examples of what pure airpower do,
the western allies tore apart what was left of the luftwaffe as well as any transportation structures left in Germany.
How can the P-63 have an impressive kill sheet if neither the Luftwaffe or japanese bothered to go up in the air? Simple fact is neither could, if they did they were quickly shot down.