"out turn" is a rather vague statement, yes?
btw.... in the Spitfire family the Spit16 is the 2nd worst turner, only the Spit14 is worse. With that being said, it still out turns most planes in the game. Mind you half of the battle is the speed in which the turn is made. The La7 is prime example. Many planes can out turn it but the La7 is so powerful that it make make a wider turn and keep the same rate as a plane turning a tighter circle.
Regarding the 109F-4, I think it is the best knife fighter in AH's 109 family. Light, nimble, forgiving (for a 109), climbs very well, speed, etc, etc. It's draw backs are the loss of control at high speed and the lack of "1 punch" knockout firepower. The single 20mm and dual .30 cal MG's are not the poster child for bringing down enemy fighters. The center-line mounting is nice, but the rate lack of deliverable damage is evident. I think the planes armed with the quad .50 cals are a bigger threat in many cases. But otherwise, I think the 109F-4 is one of those hidden jewels in AH.