This movie has a compelling story. I loved the characters in it and it really feels like a family comedy. It is really funny if you can understand Chinese humour. I, personally love it and prefer it to American humour, so I enjoyed this tremendously. This movie also's got heart and it's always great to see things working out for a few poor folks (this rarely happens in real life). Point is it's a story about a poor father trying to raise his kid to be an honest and respectful man, but kid wants more and when he finds a cool space alien that looks like a toy, he is counting on the alien to make him rich, powerful, etc.
Some people said that the kid is just spoiled and so the movie is crap. Well, those people missed the point. Movie is not about kid per se, try to think more broadly. That being said, the movie is fun and cheesy and touching. One of the best movies I've seen in a while.