This is my favorite one piece special so far. I wish they make five hour long one piece specials, because to me the longer one piece is, the less I'll be checking on the clock. Compared to other one piece specials, this is simply funnier and more well told. Under 50 minutes, it felt like a complete movie. During the first part, you get to see luffy and his nakama on stage acting and toward the end you see them fighting the marines. One piece usually don't have light hearted stories where you can just sit back and enjoy the show without knowing something bad isgoing to happen soon or some annoying villain would pop up. Remember the rainbow arc on the spa island? That's what I mean. Even though this too has a pretty annoying villain, the atmosphere remained "friendly". I mean the kind where you don't want to throw a hack at the clamoring crowd or at the villain. The story has a good beginning and a good wrap up too, and nothing felt rushed or extraneous. It's not too boring either.
If you've watched other one piece specials and aren't a big fan of them, I suggest give this one a try. At least I liked it a lot better than the other ones.