Terse, Not Simple
The book is quite terse and is often not that simple. There are too few examples. Definitions are given but seldom well motivated. There are exercises but you need a different book to verify your answers. Footnotes are held to a final chapter outside of their context. I frequently found myself needing to consult outside material. The focus was too much on the notation rather than on meaning or utility. I like brevity, but not at the expense of clarity and understanding. (For reference, I took linear algebra, vector analysis, differential equations, and other classes in university several years ago, but not any courses covering tensors.)
The book looked nice on my kindle. It was very legible. I liked the explanations of the coordinate systems and their diagrams. I learned new things about, for example, the permutation tensors and other topics. But, the book could have been more helpful.
Topics that could be explained or motivated better include covariance, contravariance, Chrostoffel symbols, the metric tensor, and more.