I've watched many spit14 auger or have killed them using spit8, spit9 and spit16 becasue players try to fly it like the other 3 spitfires. If it becomes unperked, just like the G14\K4 there will be a small cadre of Uber Aces. The rest will be defeated by the spit14 itself or choose not to fly it becasue of it's exacting requirements to succeed with it below 15k. Most will burn off their fuel above 15k relying soley on it's WEP as their best ACM manuver.
You can always tell when you are chasing a neophyt in one. It wobbles around alot during manuvering and stalls on the turns.
I think unperking the Tempest or F4U-4 would be a mistake. Unperking the spit14 will make the G14\K4 drivers work a little harder.