I'd give it a really solid +2.
One side winning all four frames indicates to me there is probably some kind of design, balance, or scoring deficiency. I prefer historically accurate settings, so this plane set was too much of a stretch for me. Also I like more variety - this one was just four frames of the same mission - escorted high altitude heavy bomber strike.
The terrain and cloud settings were superb. Fighting in and around the clouds was fantastic.
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