I like Cubaris murina for moist temperature and tropical setups, but you don't get to see them out and about very often. Armadillidium maculatum and vulgare are better for CUC with more visual appeal, but they appreciate slightly drier conditions with more airflow than Cubaris murina & since they're not as secretive there's a higher chance they'll get eaten if being used as a CUC for a creature that eats bugs, so it's not exactly a one size fits all kind of thing, hence why I'm asking you what setup you're asking about a clean up crew for.