I will tell you my own experience draw your own conclusions - before I get slated am not recommending any particular method.
I got a set of the Pooleys PPL books and also the PPL Confuser. The only book I read taking me 2-3 days was the Human Factors one - arguably the easiest one. It was the only exam I failed.
After that I discarded the books and only used the Confuser - knocked them out at about 3 exams every 2 days averaging above 90%.
My opinion us that the Confuser is all you need to pass the exams the explanations in the answers are very good. You will get the real knowledge that you need from the actual experience in the air.
Don't even get me started on the whizz wheel, brilliant in its time, totally redundant in today's world.