I like them both. In the past there were two types of vacations: relaxing trips to the beach, or non-stop land tours of new places, which can be tiring. I think that's the beauty of a cruise: it's the best of both worlds! Sea days for relaxation, port days to discover exotic new places.
And some port days are better than others - there are certain ports I'd love to spend days and days in, while there are others (Nassau, I'm looking at you) where I wouldn't mind just staying on the ship.
Land Cruise, Britain and Belgium