The book begins by a three-part preface which makes its aims very clear. There are large exercise sets throughout the book. The exercises are well-integrated with the text and vary appropriately from easy to hard. At the end of the book there are useful hints to selected exercises. Perhaps the book's greatest strength is the author's zeal and skill for helping students write mathematics better.
Careful guidance is given throughout the book.
Basic issues like not abusing equal signs are treated explicitly. Attention is given to even relatively small issues, like not placing a mathematical symbol directly after a punctuation mark. Thus students can see many examples of what they should think, what they should write, and how these are usually not the same. I am currently using A Concise Introduction to Pure Mathematics , which I recommend. On the other hand, you may very well share the opinion of many that transition courses should focus sharply on rigor and basics.