The problem with this movie is it wasn't self-aware.
You take a movie like Zombieland. It was simply amazing, but mostly due to the fact the movie was self-aware of its crazy plot.
Or the cult classic last year Scott Pilgrim VS The World. If that movie took itself seriously it would've been retarded. But these movies give us hints that the actors are in on the joke and it makes it all the more hilarious to get lost in the surreal story.
But here, I felt like they were taking the plot a bit too seriously. Perhaps if it played out more like a "how to" video on how to rob a bank and survive from getting blown up, it would've helped a lot. But because the movie isn't self aware, it took away the appeal for me.