I personally liked Heresies. It has a lot of strengths as an introduction to heresy and why it matters. It goes over the four major christological heresies and why they are a big deal—and, if you care about your life with Christ, they are a big deal—and then delves into some heresies of church and individual life. The chapters are short—you could read one over a long morning coffee—and they are well-put-together. They are also very readable. There is not much theological jargon, only the bare minimum necessary not to confuse the issues, which are in fairness fairly subtle at times. Moreover, the descriptions are very accurate, both from the historical and theological standpoints.
The weaknesses of this book prevent it from being a five-star book, however. First, it is unabashedly intellectual. These are heresies of faith, in the sense both of understanding and trust. They are not heresies concerning right living or right relation to the world, except in the attenuated sense that all faith is tacitly related to right living and right relationships. The authors are apologetic about this, but the weakness remains. Second, the book is based on a series of sermons, and therefore the chapters do not always cohere or flow into each other. The editors have attempted to make them flow better and to include cross-references between the chapters, but even so, the book is best read as an occasional read, chapter-by-chapter, rather than straight-through.
The third weakness is that the book is meant to address anxieties in churches of explicitly orthodox and catholic persuasion. All of the authors except two are Anglican, and the two who are not are Roman Catholic and Quaker. The issues involved, therefore, are of great interest to Anglicans, Orthodox, and Roman Catholics, and perhaps to some extent to Lutherans and members of peace churches, but they are of passing interest at best to most Calvinists, Baptists, and Evangelicals. Basically, if you don't buy into the Creeds in the first place, you won't care about the issues involved, even if you understand them. It's easy enough to argue, as I certainly would, that even so-called non-creedal churches are profoundly shaped by the outcomes of the first four Ecumenical Councils, and that their theology implicitly includes the Creeds and the Chalcedonian Definition whether they admit it or not, but the fact is that they don't admit it. Thus, it is of limited importance.
However, to the Anglican especially, but also to the Orthodox or Roman Catholic believer, or even a non-creedal church member with an interest in Patristic matters, this book is worth reading. I say especially to Anglicans because we are the inheritors of a deep and wide tradition just as much as Orthodox and Roman Catholics, but we are not so beholden to a dogmatic structure as they; this puts on the individual believer the onus of investigating and forming right belief, with the help of their brethren and clergy. I think it's also suitable for a somewhat sophisticated church book-study group.