Instruct: Classify a given review into positive or negative sentiment.
Query: An excellent introduction

This book is not "filled with mistakes". I checked out Pat Missin's review of it (it's in the "Fairly Frequently Asked Questions" section of Missin's website (which is excellent, by the way)). There are a grand total of three mistakes; they all involve misidentifying the type of harp used on a particular recording, and none of them will damage or impede the reader's learning how to play blues on diatonic harmonica.On a more positive note, Glover's book is an excellent introduction to a variety of blues harmonica styles. To quote Pat Missin, it is "well worth ordering from amazon.com".