They will devour your feather dusters. Not sure if you have any of those.
If you have aptasia they will hopefully get rid of them.
May not. :-(
They are difficult to acclimate.
Would recommend they are the largest fish in your tank.
They make firefish seem mean and ornery. :-(
Make sure it is eating heartily at the LFS.
Buy whatever they are feeding it.
For long term survival, more than a year, they need lots of clams.
Ours is small and I spend 10 minutes a night cutting them up and hand feeding him bits of clams off my fingertips.
If you are used to tossing in a cube of frozen then calling it good, this is not to fish you are looking for.
If hand feeding your annoying, finicky fish sounds like fun then definitely recommend it.