The wonderful stagecraft is not in question. Look at those life-size horse puppets. People are actually riding them while they're articulating in all the right spots. The projections of hazy battlefields and period costumes look great as well. The issue is whether or not the play's script is any good.
The story is a very simple one. Joey's family has to sell his horse to the French cavalry at the start of WWI. His horse's rider dies in battle and Joey, despite being too young to enlist, goes on a quest to bring the horse back home. While the horse and WWI backdrop can allow for some impressive visuals, is the narrative about the horse strong enough to sustain a long theatrical production?
This is, obviously, not the show you go to for plot. Like The Lion King before it, when a show has so much innovation in design and storytelling techniques, you can easily forgive a weaker book. The trick is convincing the audience that this simple story is as grand and impressive as the puppets prancing in front of them.
There have been a few known changes to the play for its Broadway transfer (a singing balladeer, for example, switched from male to female) that could tighten up the intricate production.
But seriously, if you could get heavily discounted tickets to see those puppets manipulated live onstage in battle scenes, you'd go, wouldn't you?