Another major factor influencing the performance of the two aircraft is the fuel they were consuming. The better the fuel, the higher the boost, the more horsepower generated by the engine. In this regard I think the Spitfire always had a leg up on the Messerschmidt.
Over the time-span considered, I'd say it's was a tie between quantity (Me-109) and quality (Spitfire).
Another major factor influencing the performance of the two aircraft is the fuel they were consuming. The better the fuel, the higher the boost, the more horsepower generated by the engine. In this regard I think the Spitfire always had a leg up on the Messerschmidt.
Over the time-span considered, I'd say it's was a tie between quantity (Me-109) and quality (Spitfire).