The ZU-23 is already OP. It was balanced for sluggish console controls, and the default allowed sensitivity in the ingame config. I and many others crank ours up by editing the config files, so it's fucking godly against air if anyone manages to reach it. I deal with it by reducing it to a couple missiles' worth of health and firing a couple at it if and when someone gets on it, but it's still fucking infuriating. I'd be fine with it if it didn't kick your aim around so much.
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