Silman's book is structured in blocks. Material is presented for players in a certain rating group and he expects them to master that. As the player increases in strength and moves up in rating, he is given a new block of material to study and thoroughly command. And so forth up the rung.
I have looked at the book and I suppose it's OK, but I won't buy it because I have a well stocked shelf of endgame works.
Dvoretsky's book is superb but will only be of worth to quite strong players. He presents theoretical positions which the reader must assimilate (not as many as one would think), explains endgame principles and provides numerous exercises throughout the text. The use of blue and black font and bold font help the reader easily identify the important ideas, principles and positions of the text.
My first endgame book - and it is a timeless classic - is "Practical Chess Endings" by Paul Keres. Keres presents positions of practical value and explains the principles in an engaging manner.
Karsten Mueller and Frank Lamprecht's "Fundamental Chess Endings" is a one volume encyclopedia/textbook which covers the essentials (positions and principles), was computer checked and has exercises throughout. Mueller has a Chessbase DVD series out on the endgame too. He is a noted expert on the endgame and contributes on a regular basis for chessbase.com and has a monthly column at chesscafe.com.
van Perlo's "Endgame Tactics" presents a whole zoo of outstanding tactics in the endgame and would go well with whatever book you choose to buy as your instructional manual.
John Nunn wrote a book on tactics in the endgame too; his newer effort is a 2 volume endgame work, which was used and praised by Levon Aronian when he was preparing for the Candidates last year.
For sheer classics, there is the 5 volume work of Averbakh, albeit it is a bit dated and quite technical; or there is Levenfish and Smyslov's "Rook Endings"; or Edmar Mednis' "Practical Endgame Lessons".
M. Shereshevsky wrote the two volume work "Mastering the Endgame", which collects simplified positions/endgames which result from the various openings and arranged them thus. It is an excellent work in that learning openings also includes knowing the sort of typical endgames which can result. He also wrote one of the finest books on technique: "Endgame Strategy".
A collection of annotated games by noted experts is also good. There you see the endgame in practice. Smyslov's "Endgame Virtuoso" is a good start.
Finally, Glenn Flear's "Practical Endgame Play - beyond the basics" is a 500+ page book covering the variety of 2 piece (and pawns) endgames that can arise. So one chapter could be R+B+Ps v. R+N+Ps; whilst another is Q+Ps v. R+B+Ps; and a third is 2 Bs+Ps v. B+N+Ps. The examples are from the past two decades and from the games of 2600+ GMs. Flear provides interesting statistics and observations on these types of endgames. A very practical book which, like all great endgame books, will increase your understanding of chess in general.
As you can see, the endgame is actually rich in excellent reference works, games collections and instruction on technical and theoretical endgames.
You won't regret studying endgames. They are lovely in their own right.
I've heard mostly of two books from all I've asked but I figured I would ask for your opinion. I'm most commonly reccomended:
Silman's Complete Endgame Course - Jeremy Silman
Dvoretsky's Endgame Manual - Mark Dvoretsky
If you have a good opinion on either of these I'd love to hear it! Also If you know of both I would love for you to tell me which one is better!