A beautiful book with swell photos and illustrations that will look
great on your coffee table and won't offend your guests. An
excellent addition to a thorough library on the subject, especially
if you are already convinced that a commercial composting toilet is
what you want.
The reason I can't give it a "5" is that I felt that, while
home-brew systems are discussed, the content was a little biased
towards commercial systems. When you consider that one of the two
authors sold them for a living (and perhaps still does) this is
less than surprising.
Contrast this to Joe Jenkins' "Humanure Handbook" (also available
from Chapters) which explains a more down-to-earth approach that
involves a bit more work, but can be implemented for little more
than the cost of the book.
Both books include valuable sections on graywater.
If you can afford it, get 'em both. If you think expensive
fibreglass will make better compost (it won't!) get this one. But
if you prefer to get down to the nitty-gritty, and/or your funds
are limited, go with Joe!