I have B.opercularis and can share both good and bad.
The bad, when maturing from juvi to adult he bullied and killed my C.johnsoni.
That said, the johnsoni is a fairy and very timid.
Today the opercularis lives in peace with a H.cosmetus and some other small fish (clown goby, guam chromis, mandarin, lightening clown, & bangaii cardianl).
The other thing worth noting, I'm 90% sure he is the one that ate all the decorative shrimp in the tank (cleaner, sexy, anemone, etc)....and hermits...and small snails. Granted, I'm sure the cosmetus joined in to finish the job.
In the end, beautiful fish for the right mix of inhabitants~