Comment Re:At the same time (Score 2, Informative) 323
I'd look at some other sources if I were you.
Fighters with the guns pointing forward had been the norm since the middle of WW1. One example was the Hawker Hurricane, which was in service before the Spitfire was developed, and which outnumbered the Spitfire by about three to one in 1940. Both were generally considered inferior to the Me 109.
What really made the difference was radar plus Dowding's organisational system. Oh, and home advantage.