There were a lot of serious runners on the Serenity and it was quite a distance around the ship. A mile? I can't remember. But if that's important to you will like that. The Symphony was the same layout only smaller.

While I'm at it, the Serenity didn't come off as big ship. The ship was full part of time and there was really never any lines. The buffets were divided up to 5 or 6 tables so I never waited.

One important point that I agree with is that the service is very Europeon. Which if you aren't used to that, it can be difficult. Takes some getting used to. There were not very many Americans that worked on the ship.