I'd check out www.castawayclub.com for more info on prices. As for a massage on the ship vs Castaway Cay...I'd probably choose a time on the ship, because the time on the island is so limited (plus I wouldn't want to be sweaty and sandy)...I know others have posted that the cabana massage is unbelievable.
That's my opinion...I'm sure others can contribute their point of view too.
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