Good guide with modern-day examples. The theory part was flexible in using idioms in sentences and different contexts (newspaper headlines, dialogues, e-mails, horoscopes) and therefore avoiding monotony.
The exercise section was mostly good, although in later units I wished there had been more tasks, since the idioms were a tad more difficult and since those units also begin to focus on idioms having a common word (hand, heart, life, death etc.), so they all kind of mush together even after finishing the designated tasks.