I recommend this book because it not only has the sinnoh pokedex in it, but also the national pokedex. It explains things very well and gets you through the game faster. The only bad thing with it is it has 621 pages.

I purchased this book for my 10 year old son who is a pokemon addict. He absolutely loves it. He uses it on a daily basis and will even "read" it while traveling in the car.

This guide is just loaded with information and most of it is well organized. The only problem I have with this guide is that a lot and I mean "A LOT!!!" of the text is SO small that it's almost impossible to read without a magnifying glass.