Oh and about the Aptitute books, they themselves say it should never be a replacement for course given handouts, notes, and essential textbooks.
Maybe I'm being a bit cynical here, but if they truly believe that (and aren't just paying lip service to the official university policy of advising against the purchase of student-made resources), then I cannot see how they view their own resource (the aptitute books) as a valuable addition to the HSFY student's existing resources, given that it covers nothing that isn't in handouts, lectures and the textbook. I just wonder to what extent the writers of aptitute are driven by a desire to genuinely help HSFYers (and not just make money off their desperation).