We've brought water with us or ordered a case on the ship on all of our cruises. The ship water tastes fine, but we've discovered it tastes better if you let it run for a couple seconds before you fill your cup -- could just be a mental thing for us. Mostly, we like the individual bottles for excursions. They are a bit easier for us to manage, and you can throw away empties as you go to reduce bulk in your backpack or whatever you might be carrying.