I'm also going through the exams. I have airlaw, about to write Human Factors.
I studied airlaw until I could answer the questions in the back of the thom books when my girlfriend read them out while we were driving places. I then got the confuser and to my surprise started scoring quite low. This was because I was skimming the questions and answering too quickly instead of really taking the time to understand exactly what they were asking. I also signed up to airquiz.com and did a few practice tests on there which caused me to score low yet again! I hit the books again out of fear heh. Eventually I was getting 85% just about every time on the airquiz site. I wanted 100% of course but it seemed out of my grasp so I wrote the exam at this stage of preparedness. I passed with 87% which was very close to what the mock exams were indicating I would.
A couple of the questions asked about things I had not seen before such as minimum equipment levels for certain flight conditions. I took a best guess but never did find out which ones I got wrong, my instructor said they don't go over the questions you get wrong or didnt understand (bad idea in my opinion - surely a contributor to unsafe flight!!). Still I passed and I assume the things that I hadn't seen before (in either confuser, thom, or airquiz) were just things I would have picked up had I studied from the AIP direct (which I actually did do to a point but that thing is MASSIVE and very difficult to determine exactly what applies to lil' ol' PPL students like me).
splatt