Assuming we are limiting it to prop planes, in a scenario setting, the best are 190D's and 109K's. Which one depends on pilot preference. I've flown them both a fair amount in scenarios and prefer the 190D because of its excellent handling at high speeds, excellent roll rate, and lots of ammo. They are fabulous planes for a scenario environment (many on many fights, high alts often involved, high speed often involved, etc.). The speed, handling, lethality, and ammo load give you the ability to get in, flick quickly to position for shot, give a good burst, flick to a new position, shoot more, etc.

