The first thing to mention about this book is that it's not an actual printout of George Lucas' original screenplay that was turned into the 1977 blockbuster film. This is more like an annotated screenplay of the 1997 Special Edition re-release of the film, and with that leads to several minor problems.
Firstly, being based on the Special Edition of the film, the screenplay follows the Special Edition cut of the film exactly. There are no extra scenes that didn't make the final cut, no dialogue exchanges that played out differently in the script compared to the film. Everything that happens in the film is here in word form.
Secondly, as it follows the film so vigilantly, everything from the film from character dialogue to the descriptive action to even the one-off shots of Star Destroyers or The Death Star or even The Millennium Falcon simply travelling through space are included in the script.
All-in-all, this isn't precisely the screenplay but the film reproduced into a basic script. That being said, it serves as a great starting point for seeing how a screenplay should look, even if the page layout isn't correct. For those just starting out in learning about screenplays and writing them, this is a good jumping off point.
This is an exciting and refreshing look into your own dreams. It is full of action with a touch of romance. It allows your mind to be transported to another time and another place. You become part of the emotion that the charachters create.