Although Max Reger's 100+ examples all end with some flavor of either a V-I or vii-I chord progression, I would classify more than half of them as transitions from one key to another rather than a transition from one key to another with an exclamatory cadential ending. The book is a usable reference, but not for the beginning student of harmony or music theory. Line and smooth harmonic transition in his examples are frequently sacrificed apparently in the interest of brevity.
Despite the negativity of the paragraph above, this little book proved to be a very valuable addition to my reference library, but not in the way I expected it would. I bought the book to use as a quick reference for a modulation while I was composing music, but found that it was far from the cookbook tool I expected. Some of Reger's examples proved to have either a harsh, incomplete, or unconvincing cadential sound, and that spurred me to work to make them less harsh and more complete sounding to the ear with a strong cadential ending.
In those efforts I found the real value in Max Reger's work. I reworked 63 of the 100+ examples to make each smoother, more complete, and/or more convincing, and that's where the real learning took place. I now have a "library" of modulations which I can draw upon whenever I need to. I strongly recommend this book for anyone with an interest in music composition or analysis as a study guide to really teaching yourself all about transitions and modulations. However, I make this recommendation with a strong warning that it is not a cookbook for writing music with smooth, flowing transitions.
Spend the $7 for the book and then use it to teach yourself modulations and transitions by creating your own set of reference modulations based upon Reger's. Be economical and try to improve on an example with as few additional beats as possible. Unless you are a budding Mozart, that process may take a considerable amount of time, but it will be time well spent.