<p>Recently, I have been looking for some SAT subject prep books online and have noticed how siginificant the price differences are between 2007 books and 2009 ones. </p>
<p>For example, a SAT literature book by Kaplan 2007-2008 sells for $5.68 while a 2009 book by Kaplan sells for $18.89.</p>
<p>I am looking for a SAT chemistry and literature book and I want to know if the content in 2007-2008 editions is that much different from the 2009 books. I am sorta drawn to the cheaper books, you know? </p>
<p>What do you think?</p>