This is an odd book, that's for sure. I have never read an entire book of questions and answers. However, even if I vehemently disagree with Kreeft on some topics (such as Christian rock-there is some good and profound music in that genre, even if it doesn't measure up to classic hymns and chants), he's definitely authentic and honest.
I don't anticipate this converting any atheist, but I don't think that's the point of this book. The point is just to show the basics of who Kreeft is. To that end, it's done pretty well. Most of it is accessible, though there are moments where I had to read things over a few times. I would also like him to explain himself further at times, for example when he callls music "the most profound of all the arts."
However, this is a generally interesting series of questions and dialogues which illuminate Kreeft's personality and way of looking at the world. I definitely think his answer for why Catholics don't believe in reincarnation was my favorite Catholic-related question (though I'm probably biased because I love the idea that Catholicism sees both body and spirit as good and that was used to explain it). Other than that, his thoughts on Chesterton are pretty good as well.
Ultimately, if you're not Catholic, this will probably be less enjoyable for you, but there's still some good questions and answers here.