While I am highly suspect of smaller publishing companies who seem more along the lines of a self-publishing company, I found this book to be fairly sound theologically and exegetically. I find the subject matter to be unique in the sense that most people write for a particular historic understanding of worship with an appeal to the Bible. Dr. Bartley, on the other hand, appeals to the Bible in order that we may worship God according to what pleases Him.
I cannot recall seeing a book or bible study devoted to solely to understanding what the Bible says about worshiping God and therefore would recommend this volume to be added to your library for a couple of reasons. First, the author sticks to the Bible alone for his study material. Second, he writes with passion and humility on a topic that, while it has been divisive in the past, should be at the heart of everything we do in our lives. Obviously, you will not agree with everything Dr. Bartley says, but that is not the point of his book. His goal is to offer a systematic and biblical study of what kind of worship it is that God finds pleasing. I believe he met his goal.