It's not OP. It's fine, because:
1. It has a setup time, so you can see it comming and have plenty of time to duck/run;
2. It can be easily wrecked by a few PTRS/AT nades shots, not speaking about anything higher than that (like AT gun for instance).
3. It involves a certain quantity of risk because: it's more easy to be destroyed than a Puma or a PZ II and on top of that, it really delays your puma/wurframen, T4, or any other fuel based unit, you name it.
...4... not everything OKW has it's OP, really

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