I seem to remember using the Thom's it was about 2 weeks doing 3 hours per night for each of the subjects apart from Human perf.
The Human perf book I skimmed through whilst on the bog one day and got 95% in the exam so 10 days is a bit of an overkill!
The rest of the exams I also averaged about 95% without having the PPL confuser so if you use that too you should have no probs.
Best of luck
UA