I had two of them myself. Together, they ate 1lb of seafood each week! They were wonderful, but grew too big so I sent them to the denver aquarium where they are swimming in a 100,000 gallon aquarium with 300 of their closest friends.
Overall, they cost a lot, poop a lot, and swim a lot. Be prepared to upgrade your tank, and do lots of water changes. They are wonderful however, but just know what you are getting into.