While I personally found this book useful, I’m skeptical about how helpful it would be for its intended audience (beginners with limited time to study).
I’m fluent in Spanish and studied Portuguese formally for a year, but fell out of practice, and used this book as a refresher. It was useful in this regard, but that knowledge also made me realize how quickly a beginner would be lost reading this. Part of the problem is the layout. Almost from the beginning, the book contains complex sentences in Portuguese, such as on page 17: “Quem pode esquecer o perfume duma rosa?” (Who can forget the fragrance of a rose?) Conversely, basic expressions like “bom dia” (good morning) and “Que horas são?” (what time is it?) don’t appear until page 78.
Another major flaw of this book is that it will often give vocabulary and sentence structures that are specific to either European or Brazilian Portuguese without indicating which region it would be used (or not used) in. Portuguese varies a lot more from region to region than, say, Spanish, to the point that some grammatical structures differ between the two, and it’s really important to be aware of these distinctions.
On the positive side, the book does a lot of things well, such as its charts of irregular verbs, and a simple table explaining grammatical terms that may not be familiar to a layperson.
Just be aware that, if you are approaching this as a beginner, it would only be effective in conjunction with a lot of other material for learning Portuguese.