Prior Exams - How far back to review? practice, 2005, available, previously

NakedPuts

Prior exams going back beyond 2007 were available previously on CFAI website. I have gone as far back as 2005 but debating if I should go back further or the questions on older exams may not be relevant?

I personally think that reviewing/solving these exams and solving EOC questions is a much better use of time than Sch practice volume 2, maybe volume 1 as well.