nah

I would say yes OP, not necessarily yes cheat. It is quite OP, since it costs a small amount of Steel for a huge amount of resources. But if you leave everything at the default settings, I wouldn't consider it a cheat, since it has a limited lifespan and you can't place it just anywhere.

i use for chunk farm, impossible to leave the base to mine then comeback, too risk

feels like it

Is it op? Probably.
Is it fun to watch my slaves mine everyday? Yes.