Go with the Cleaner Shrimp, the cleaner Wrasse are hard to keep alive in captivity and not as abundant in the wild.
In fact get two, they will lay eggs that can feed the fish and corals.
Cleaner Shrimp are hermaphrodites, so you do not have to worry about getting a male and female.
We added a second one a month ago, and our larger one has been carrying eggs ever since. Every so often she will beat her tail to knock some loose.
Phishy usually has them, and for a good price ($19).
Jack's has them, but they are more expensive ($25).
Aquarium Adventure charges $30 for very small ones.