cool - I didn't think this would spark discussion.
I picked up five trochus at F&F because I couldn't find astreas, and they were all dead the next day. Aquatic World out here in Leesburgh has an awesome cleanup crew selection, although they are $3 each, which adds up fast. I still have the orginal 7 scarlet hermits and 2 ceriths I bought from them almost a year ago, along with every fish I've ever bought from them.
Occasionally I will find the astreas upside down, but they seem to be able to protect themselves because after I right them they keep moving around. Remember, in nature they are food, not pets so it's not a big deal to just keep replacing them.
I have a feeling I lost my mexicans becuase the tank temp stayed over 80 all summer. Not sure if I even need to replace them now and didn't like how they kept knocking over frags anyway.