I'm a great fan of the fighting conch...they're an honest, very hardworking sand-cleaner that will clip hair algae at the roots, and if they're burrowing, they're probably still eating. I don't think mine has rested more than 12 hours in the last two months. Hermits have flipped her over: she tucks in and ignores them...
Blueleg and scarlet hermits are great fun, IMHO. One of mine in particular will pick up a snail and go all over it like an ear of buttered corn, then set it down and go away. The snail will be unscathed and cleaned of algae. Astraeas can get places the big snails don't reach easily, and they really scrape. But the big turbos are real generalists, while the 'moon' snails specialize in glass.