I think td2 has a good idea here. No one is suggesting that it isn't important to study. I for one have not spent that much time on FB questions yet was able to pass the first eight I did first time. However having just taken the Instruments, Opps and Radnav exam I can honestly say that no amount of study gets you ready for the obtuse way that some of the questions are asked. The only way to be prepared for them is to see feedback.
Believe it or not I agree with Mr Magoo in as much as Feedback has to be taken with a pinch of salt. The feedback on my site is definately not 100% accurate and the truth is I have probably remembered the questions I felt were tough for me, leaving out the ones I found easy because in the exam I didn't have to think too hard.
This said though you can never be too prepared. Furthermore I smiled to myself in the exam when I saw a question on tornadoes that I had seen on Big Red Jumbos site, and another question on Magnetism that I had seen on the web.
In the run up to the exam when you have done all the possible reading that you can, having a bank of questions to trawl through can be a lifesaver.
Finally lets not forget that not everybody taking these exams is studying at a large establishment with 1000s of questions. These guys would be very grateful for anything they can get hold of, web or otherwise.