I ordered this book in 1993 and studied the language solely based on this book. This was a FANTASTIC book to use to start learning the language. I am a non-Samoan who has been speaking the language for over 17 years. Because I had my husband speak with me daily in Samoan, I had an extra advantage as I was able to practice the intricacies of the language.
One thing I noticed is that if you are NOT very good in English grammar (understanding what first person exclusive is, etc.), you will have a difficult time teaching yourself a language from a book! If you are not patient with learning and memorizing, you will also have a tough time! Some people learn better from visual sources (books) and others learn better through auditory means (orally)...I am a visual learner, so this book was a very successful tool for me.
Bottom line...learning another language takes time, patience, and practice. I highly suggest this book...it is a great tool for getting started with the Samoan language. Take it from someone who used it...successfully! :)