This is a well-researched book on the whole, with copious references to chapter and verse. In effect, it uses the Bible's own words against it, with plenty of insight from the author. Although many points can be casually dismissed (the bats-are-birds claim is weak, for example), it still contains a great many points of fact that might make the average evangelical take pause. Sam Harris has said that changing minds in real time is extremely rare, but if you can plant the seeds of doubt in their minds, the future payoff for that person could be great once they have liberated themselves from the shackles of religion.
Speaking as an evangelical Christian-turned-atheist, I will caution the potential buyer that you should not debate with a well-trained theologian using this book. You simply can't. It's not that the arguments in the book are all bad - most are sound to a reasonable person - but remember that these people have a tricky deity. When you can hand-wave and explain away any contradiction ("METAPHOR!") or apparent malevolence ("CONTEXT!") with the kinds of mental gymnastics and logical contortions that theologians get degrees in, you face a Sisyphean task. Don't bother with these people. Just like how Star Wars nerds can retcon Han Solo's script mistake in Episode IV ("By parsec he meant shortcut in distance, not time!"), the versed theologians are by and large beyond reach. At least we can take some comfort in the fact that most of them aren't young earth creationists.
Buy this book. It is well worth the few bucks, and you could learn a lot. The formatting could be better, but it's totally readable.