Depends - do you prefer to learn about native culture or native flora? What other excursions are you planning - one might provide an experience your will have no where else.
We did the aerial tram in Dominica - very cool, but I'm into that type of thing. When you are about 1/4 mile from the start you hear nothing manmade at all.
All I ask is a tall ship and a star to steer her by; John Masefield
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014, Regal 2014
Star Clippers: Royal Clipper 2015