I bought this after listening to Pimsleurs learn Korean audio course which I would also recommend as a great introduction to the language. The book is well paced, it doesn't throw too much at the reader at any one time which makes it easier to recall previously learned rules without tripping over yourself and mixing them up. I feel that this is especially important for a language which has such different grammar from English. I've seen other books which seem to have mountains of information crammed into them. These books didn't appeal to me as I'd much rather a more structured and gradual approach to learning Korean (as I'm learning through self-study) and after completing this book I think that it does that job quite well. I don't mind buying a series of books that increment my knowledge slowly. One a side note the pages are nicely designed and structured and overall the book looks well, some people obviously won't care about this but when you're studying a difficult subject it can be a welcome attribute of any textbook and makes it seem less arduous to get through.
One thing I would recommend is writing out all Questions and Answers and Narrations rather than just filling in the blanks in the book as otherwise you won't have written out the words enough to remember them properly.