On balance this book can be recommended for the beginning guitarist, or the non-reading guitarist who wishes to learn to read standard notation, but not unreservedly.
I'd disagree with the reviewer who thinks that this book (the first of a four-part series) is unsuitable for children. I would say, however, that it's unsuitable for anyone who lacks the guidance of a skilled teacher, since there are, as the authors' introduction concedes, no instructions about holding or tuning the guitar. Furthermore, terms such as "rest stroke" are not defined and the techniques they refer to are not described in practical terms.
I cannot understand why the authors have chosen to introduce dynamics so early, since producing dynamic shadings on the guitar requires far more in the way of playing technique than any beginning guitarist is likely to possess. This is not to say that dynamics are unimportant; quite the opposite. In fact, they are too important to be introduced at a stage when the guitarist is mostly struggling with finding and producing the simplest notes on the guitar and, lacking the technical control to deal with dynamics adequately, will only find them distracting and confusing.
At 16 pages (of which only 13 are devoted to actual playing studies) the book (like its companions) is a little on the skimpy side, but at this early stage in the study of the instrument this is probably no great disadvantage. Anyone who, with suitable guidance, completes the four volumes should be ready, if they so wish, to tackle larger and more ambitious guitar methods.