last two books give you the foundation if you are weak in verbal and the math , and for sure you need other books to give you strategy and focus on advanced topics Kaplan 800
doesn't contain strategies but contains 600-700 level questions and few of +700 question .
i think a kindle version is available :D
How can i lose my faith in life's fairness when i know that the dreams of those who sleep on the feathers are not more beautiful than the dreams of those who sleep on the ground? - Jubran Khaleel Jubran