hermits love a free meal thats for sure, pretty sure i've read that theres not one species that won't take advantage of an upside down snail. they're also annoying when you feed anemones/ lps as they usually start climbing on the coral and pciking at it, which really annoys it. for example a condy anemones worst anemone just happens to be a hermit
, definitely would'nt deem them reef-safe, more evil than anything..