Before I got the ATI book, I bought the Kaplan and Princeton Review books. They're ok, but I liked the ATI book more. The other books focus on all nursing school entrance exams and not just the TEAS, so you're going to be studying a lot of stuff that won't be on the TEAS (Geometry, thermodynamics, etc.) After taking the exam, I felt the ATI book prepared me much more. The good thing about getting the Kaplan book though would be you get to study the material all over again and take some new practice tests. Good luck!