In comparison to Lonely Planet and Let's Go guides I've used in the past, I found this guide very disappointing. The author/editor can't seem to resist inserting his negative editorial opinion about every last city, village, hamlet, mountain, forest, castle and stone in either country. Cities are frequently described by their relative degree of "sovietness" or industrial decay. Areas in the countryside are typically described by their degree of industrial desolation, pollution, tourist exploitation, and environmental neglect. Even when he has something positive to say about a particular destination, it's couched in whingeing about something negative about something nearby. Humphreys' jaundiced tone makes visiting these countries seem like a trip to the Pennsylvania Rust Belt of the early 1980s. I've read travelogues that make Chernobyl seem more appealing.
Avoid this book. You're better off with Lonely Planet.
ADDED: having been to Slovakia and Czech Republic twice now, I can say that his descriptions really are off the mark. I didn't see any of the rust belt horror show that Humphreys describes.