My first copy of this book was the 14th edition. After years of learning, researching, dreaming, and building, that book needed to be replaced. Pages yellowed, (thanks to their acid paper), worn cover, and sections falling out. What is inside, makes it an excellent book. Surely, it could not be improved much.
I decided to purchase the latest edition, and WOW! Have things changed! The 22nd edition is not just a rehash. The amount of new material is mind boggling, and honestly, to a radio and electronics geek like me, very exciting. The book is huge and heavy, and I don't think the pages will rot and yellow like an old newspaper anymore, though I can't confirm that it is acid free paper.
The book is reorganized and they spent a lot of time simplifying the looking up of topics. So many projects from the pages of QST have been added, that author and project indexes have been included. They included a CD ROM of the entire book, so you can go to your computer, and search for specific words or phrases. That is all I expected, but there are many other bits of useful software that they put on the disc, including all kinds of designing programs.
If you have interest in antennas at all, this book needs to be in your library.