Been on 4 cruises and all of them had great service with 2 cruises for us having out of this world. Getting to know the waiters is also something cool -- just being more personalized. Food quality is still superior to most cruise lines though (have you had the truffle cheese ravioli appetizer? Or the SeaBass?), and Castaway Cay is a phenomenal stop. DCL for me anyway is more about the ship than the ports, unlike Carnival which is basically just transportation.
Something cool that the waiters did for us one night was they saw how much we loved the truffle cheese ravioli appetizer, so they brought it to us in addition without asking the next night. And like I've said, just getting to talk to the same people brings them more to life than just people serving you randomly. It's that personal, intimate feel that Disney has nailed on their ships.
Besides the price, the main downsides are the pools, and probably lack of casinos for the adults, but really the pools you can do on land, and casinos can attract the wrong crowd. For a teen (and his friends), the Vibe is so so good from the activities to the counselers, to the private pool. It's just a really good setup.
But the included beverages (and actually really good!) salad wraps at the pool really help propel the ship. The fact that there is almost always someone cleaning the restrooms on the ship, or that you can see in movie movies if you so chose paired with a great dinner and a wonderful show (like Aladdin). Heck... the activities are wonderful too! I wouldn't recommend though if you have kids under 6 or 7 (and really the most fun they have starts around 11).
Of course you do pay more, but the service across the board is top notch and the ship is simply beautiful inside and out (especially the Fantasy). You really cannot get a better family ship than the Fantasy.
Funny story, as everything on the ships are free (obviously besides liquor, fine coffee, and merchandise) we went to Disney World for 1-night after our last cruise. I was going to not pay for ice cream that I got at the hotel as in my mind, it was included. Told the Cast Member that and they let me have it for free; that was very nice of him too!