Students that purchase the books do better on the exams.  With a printed book, you can highlight, make notes on the margins, and take your studying anywhere - even if you have no internet connection.  After you pass, it's also a great reference guide to have around the office!

Don't forget to look inside your online course for the discount code!  You will likely find it in the downloads section in the lesson just before this one.  The printed books are only $30 after applying the code.