Reliable sources or not.. One thing that can be more or less factual and is represented in the game (and improving over time) is the relative performances of each aircraft, it's advantages and disadvantages - this has always seemed to fit the bill, and quality control of these features are important, if you do not want to destroy the online game.
Sure minor hiccups here and there, but essentially it has taught those who have taken the time to know their favourite a/c, how to fly it to it's max. In this, IL2 has been more satisfying than any other flight sim.
