E. Feser's introduction to Aquinas' thought was exactly what I was looking for: a clear, contemporary introduction (and defense!) of Aquinas' thought which interacts with modern objections. Having read introductions by Ralph McInerny, Henri Renard, F. Copleston, Jacques Maritain, and A. Sertillanges, I can say that Feser's book is better than all of them.
First of all, Feser is faithful to Aquinas' thought. In content, Feser's philosophy is aligned with something, say, Garrigou-Lagrange might write, the difference only being style. If you think Garrigou-Lagrange understood Aquinas, then you will think Feser has, too. Most of the authors I mentioned above more or less understand Aquinas adequately, so far as I can tell. Like them, Feser won't give you any surprises by departing from the tradition (like, say, E. Stump might).
Second, Feser's book is better because it is clearer. There are plenty of thinkers who understand Aquinas decently enough---one thinks of Maritain or Renard, for example. But anyone who has tried to read these thinkers is painfully aware that their prose is not always clear. Feser has given us a book which is in a class by itself for clarity. If you are puzzled by 'matter', 'form', 'act', 'potency', and so on, then this is the book for you.
Third, Feser's book is better because it understands modern thinkers and their objections to Aquinas. Feser admirably defends the existence of God, the classical attributes of God (including divine simplicity), the immortality of the soul, Aquinas' ethical theory, and so on. Not only this, but he shows why objectors to Aquinas usually have not understood him properly. He treats older objectors like Locke, but also newer ones like Dawkins (and many analytical philosophers, too). It is especially its mastery of analytical philosophy and the issues it brings up which makes this book relevant to modern concerns.
Fourth, Feser has a list of recommended reading which is very, very useful.
And to top it all off, this book has one of the best discussions of causality, especially final causality, which I have encountered.
So, if you're shopping for one book to start with in studying Aquinas, you've found it. Or if you've read many introductions but still feel lost, this is the book for you, too. Feser brings the clarity of analytical philosophy, the relevance of modern issues, and the content of classical Thomism all together in this volume.