Does the book go into good details, or is it very general (i.e. not giving much descriptions as to the "why" behind everything)?
If this book is as good and important as everyone says it is, then I think $85 is a good deal for it (I spent a lot more on bad books while I was University!

).
I have also read the following books, and am interested in similar ones:
- Flightwise volume 1, by Chris Carpenter.
- Flight Theory for Pilots, by Charles Dole.
- The Turbine Pilots Manual.
- The Advanced Pilot's Manual.
- See How it Flies.
If you guys can recommend other books, please feel free to list them!