Well, in the BoB there were more than one 109E variants, and same with the Spitfire.
The Spit II holds the high alt cards on the early 109E and vice versa.
Spit outturns the 109E. (RL)
Speed is very similar, depending on variants. Our AH Spit is a tad faster.
Roll is very similar, depending on speed and pilot strength. (RL)
Climb is very similar too! Given the same engine performance the Spit will hold the cards AFAIK. (RL)
The 109E has much more firepower as long as the cannon shells last.
And...the 109 can bunt without losing the engine power, and also has a better dive.
That's about it.
And Reynolds, join the scenario. BoB is a blast!
(I remember me coming from the keyboard with shaky hands, lol)