My older son did both and loved both. They are pretty similar but the story is a little different. The one at YC was his favorite but he'd be happy to do either again. The YC cruise goes into Epcot and they dock at the World Showcase and get to chase a pirate. That was the part that I think gave it the edge as his favorite. I also prefer this location to easily find something to occupy yourselves for the little over an hour they are on the boat.
Yes, some kids dress up. But they also give the kids a bandana and they wear a black life vest with a skill and cross bones on it. And they'll get jewels, necklaces, and rings with the treasure they find.