It is a good little book that will come in handy especially for those who are beginners or lower intermediate, those who are on a budget, those who are studying Italian on their own, or those who hate grammar and are doing their best to ignore it. That includes a lot of people. I am personally very skeptical of any claim that you can learn a language decently without some exposure to grammar and its (gasp!) rules.
The weakest part are the first few pages, on basic pronunciation. Although pronunciation is perhaps the easiest part of Italian, you should strive to get it right from the beginning. The material here is misleading e.g. the Italian letter e is not pronounced like the vowel sound in the English word "day." The list of vowel combinations is (somewhat) valid only if they are diphthongs. I would disregard this section and look for audio guidance by native speakers, which you can find on the Internet, for example, at the pronunciation section of the BBC's beginners' course in Italian, found here.
Also, note that the little handbook makes no attempt at providing the grammar in the order in which it should be learned.
