For clep study guides I've found the reviews on Amazon to be spot on. Jack Rudman's books don't tend to get reviews as high as the REA series.

__________________
I have 18 traditional credits and 51 exam credits. I've passed Introductory Sociology 76, Introductory Psychology 68, A&I Literature 66, Principles of Marketing 76, Introductory Business Law 71, Social Sciences & History 67, DSST Drug & Alcohol Abuse 450, Biology 69, Principles of Management 70, Natural Sciences 64, Intro to Business DSST 70, Principles of Macroeconomics 67, Principles of Microeconomics 58.