Again, thanks for all the comments.
JamesD, as you said the AFE books give more than you need, so the fact that I am getting good passes using the AFE questionis and the AFE simplifier practice tests must show that it has sunk in.
Which is why I was surprised with the Confuser questions. I'm not syaing it was wholly different. What I mean is I realised that I was getting an extra 5-6 questions wrong using the PPL Confuser questions which brought me to a fail - so 68%-74% somethign like that. When I went to cross reference with the AFE book, it was simply not covered.
Anyway, I'm using the confuser now for my practice tests.