Let me preface this by saying I have cruised both lines and enjoyed them all. Princess will give you a low key, more elegant feel. No hairy chest and belly flop contests...less around the pool kind of entertainment.
While I have enjoyed the food on both, I would tip my hat towards Carnival for food & entertainment.
You know what fits better for you, pick one,and you won't be unhappy, either way...
Trip, with her book & tea!
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