the Spitfire is a beast in MP in its current state, you just can't run from or chase an axis aircraft. Which makes flying the Spit pretty unique. She climbs like a rocket, turns on a dime without loosing pretty much any speed, has brutal guns and overheating got patched so no problem here eather.
What remains is you never decide when the fight starts and ends, still to low topspeed. Good luck flying deep into enemy territory, they will boom on and your turn rate won't bring you home. You just keep sitting arround in hostile airspace... with labels on everybody will jump on you.
Axis aircraft still have all the choices. When to fight and when to retreat and go home. It is the most important advantage in my eyes. Airspeed matters!