I've heard differing opinions from my term 2 classmates last term; some liked the blue spiral book and some preferred the purple Problem Based text.
The blue is more pertinent for pre-midterm material (but the final is cumulative) and has questions for practice, some of which are used on the exams.
The purple (Problem-based Immunology) has a more clinical approach though there is a short basic science review each chapter before the clinical cases begin. There are some questions here too and some questions in the 2 texts are the same.
I think (mostly) everything in the blue spiral text is included in the course's "Summary Notes" handed out before each section but of course the text is neatly organized and easier to keep together. FWIW, I used the online presentation slides pre-midterm and used the purple Problem-based Immunology text post-midterm and did well but like I said everybody seems to have a different opinion.
I finally have my long white coat, and it is stinky...