Answers (1-3) are a must have for your library! The Bible stands firm in the face of modern scientific theories that question its truth. Answers is a great tool for a Creation World View. I have heard Ken Ham, the author, speak and he knows his stuff.
I use these books to look up questions that I have and use it as a resource for new believers that I disciple.
My kids are now starting to learn how to defend their faith, making these books key to our Bible/Science studies.