speed_alive_rotate - I used Aviationexam.com 18 months ago and found it excellent. Most of questions I faced during the actual exam (Polish CAA) were the ones I've seen @ aviationexam.com - I would estimate it to be about 95% coverage. I passed all exams at first take with a nice average of just above 90%. I bought access to this database for 6 months but used it only for 2mo.
When it comes to reading books and understanding problems vs. banking all day long: I've read all ATPL books (a set of I believe 15 by Jeppesen) and made sure I understood 99% of questions I answered when banking online. On the other hand I know people who have not read a single book, did not understood many questions and passed all exams. The choice is yours - either you want to pass or you want to understand & pass. For me the option was obvious
