I'm just curious, why is U4 so much worse in almost every important stat except altitude performance than U2? Doesn't seem to me, that with those stats it would make any sense to rearm from U2 to U4 configuration. It's also using a different bitmap. Would this be a bug or is there a logical explanation?
I'm also somewhat curious, why less armed R3 having as expected a bit higher speed has slightly worse maneuverability and altitude performance than R5.