It is worth putting ~1 cup of mild cleaning agent like distilled vinegar down your AC drain line every time you change the filter if you live in a humid area! All kinds of stuff can build up or live in that line leading to a clog, leading to a float switch cutoff or even a bit of mild flooding of your Aircon closet.
Definitely the slowest of the three IMO, but the back third of the book really gives a great conclusion to the story at large. Definitely worth finishing once!