It starts slowly then it gets really better
The beginning of the game is kind of boring. Although, after five hours of gameplay, it finally starts to become more and more interesting in its gameplay and in its new playground : the hunting grounds. And when you start climbing trees and sailing, it's really enjoyable. Even though the world of Assassin's Creed III is less refined than Assassin's Creed II's, you can't say it's not magnificient.
A really good game but not as good as ACII.