I've sailed on her 3 times and the Island once - all to the Canal. They're both great ships - they called them Panamax cuz they just fit in the Canal. Plan on sailing on the Coral again in March.
Don't miss the ferry boat excursion through the other 2 locks and over to the Pacific Ocean ... outstanding. And, generally I don't like shore excursions. Skip the train trip - goes so fast you can't take pix and then the rest of it is a lot of bus traveling.