I already explained why it has a much higher K/D. For whatever reason you guys just didn't read my post.
It is fast- faster than all the Allied planes on the deck.
It accelerates a lot better than all the Allied planes.
So, if you are ultra-cautious (figure 90% of the population), you will never die in it.
Even if you have the balls to get slow and fight (and the G-10 will outfight the P-51 and P-47, and a P-38 if the 109 gets real slow real fast), you can QUICKLY get up speed running speed should 2 or 3 Allies show up expecting an easy cherrypick.
Sure, the P-51B is right around the G-10s speed (maybe 5-10 mph slower on the deck, with the gap closing as you climb), but if you get slow in a fight with a 109 and 3 or 4 other LW planes show up.... you can't run. You can't get going fast enough to out-run them, whereas the G-10 can get the whole gaggle slow, then accelerate away.