I used this book for Calc I and II. The pre-calculus sections cover everything that you need for the calculus you'll be doing in the book. If the pre-calc section didn't cover something you'll need in one of the 'real' chapters, the book covers it in the beginning section of that chapter. Everything is organized well (in my opinion). I do agree that the way some of the lessons are explained are sometimes hard to understand but all you need to do is fight through it to try to understand. If you still can't understand, just start trying the homework & the examples & you should be able to catch on.
Some classmates were complaining that it didn't review for Trig as much as it should've (you really need to have the special angle (30/60/90, 45/45/90) concepts memorized (or at least have the sin,cos & tan of the special angles memorized), however, I do remember the author adding additional sections in the appendix that covered the Trig you need to know for the course. So make sure to check the appendix, it may have something you possibly need.
Overall, I really liked the book. I highly recommend the H Anton book for Calc III though. I had a really applicational calc III teach that NEVER did examples & never taught anything from the book. He'd constantly go off on a tangent teaching applicational stuff that was very interesting, however, it did nothing for us in regards to the stuff we needed to learn for the class. The H Anton book basically taught me the entire calc III material w/o a teacher. The way it was written made it so you didn't really need a teacher. If you're taking calc III, I definitely recommend the H Anton book (get it used though, don't pay high price based on my review. Not all books are for everyone, just b/c I liked it doesn't mean you would).