First and foremost: this is not a review of the literary quality of Nietzsche's work, but rather of this particular publication.
I've read this book several times- as I imagine is true of many of you, at various noteworthy phases of my life where it took on new and different meanings. As a result, I've read at least three distinct versions of this work, including the original German (which is a second language to me).
To begin with, this is the first that included a truly comprehensive foreword regarding Nietzsche's relationship to his works along a timeline- someone coming upon "Zarathustra" as a first Nietzsche read, or as a student, will find a lot of very helpful contextualization before they even begin reading the text itself.
Moving on to the text itself, I regard it as a much-needed modern interpretation of "Zarathustra." As much as Nietzsche's goal may well have been to parody religious and mystical trappings, the outdated language of the German-English translation is to many distracting and off-putting. This translation preserves the spirit of the work in modern, straightforward English without any liberties taken with the cultural nuances of the German or the overall storytelling style that was characteristic of Nietzsche at this point in his career.
Overall, the best "Zarathustra" you can read. The Kindle edition is quite nicely formatted, too.