For being a game devoted to "fun," the constant reminders across the screen asking "Are you having fun?" serve to make me aware of the lack of fun. I played it to the end (one end of two), and only stuck it out to check it off a list of games I have in my library. It is short (less than 6 hours). The physics of the game are frustrating (especially at the end when flying comes in). The humor is not my style, but it may be yours... The story is terrible. Making your own vehicles serves little to no purpose as the blueprints of vehicles are often good enough. They force you to build one time during the game, but that even that was limited (as there was only one real option on how to build). I do not think this is worth your time let alone money.
I should add that the time listed for me is slightly off due to steam network issues. It was less than 6 hours of play time though.