Rating: 

However, working throught the examples was hard work. Since the code for the final running application is not supplied, it is not always clear which code fragments have been kept and what has been left out. Some examples messes up the flow of going through the Photos example, and the double scaffolding messes up the rails project file structure by providing both a slideshows and a slideshow controller etc. Several of the code fragments are incomplete. The experience of getting the Photos project to work became quite frustrating.