Here's how I passed the the PMP:
1) several years of real project management experience. The PMI/PMP legitimately warns that you cannot take the PMP test by book learning alone.
2) I picked up RMC's book, another book who's author escapes me (but was similar in approach to RMC), and the PMBOK.
3) I skimmed (SKIMMED) the PMBOK to understand the topic areas. The PMBOK is not an end-to-end reader. It's a reference book, like an encyclopedia, and should be read for section topics.
4) I read the RMC book chapter by chapter and took the sample tests. I graded myself on each sample section and read the explanations for answers I missed. I referenced back to the PMBOK to cover the section from their perspective as well.
5) I continued doing #4 until I was ready to take the sample full exam from one of the books. Again I graded myself. I kept evaluating myself aginst the passing-grade percentage for the test - I had to achieve passing grade in every sample chapter test and the full exam.
6) I started the "other" book of test tips and sample exams, again referencing back to PMBOK and grading myself.
7) I began retesting myself against those chapters' tests that I hadn't achieved the passing-grade percentage initially.
In short, read one teaching book, work it through, grade yourself as you go and reference the PMBOK for charts, tables and discussion. Then do the other teaching book similarly. Then retest yourself to raise your overall score to passing.
I passed the actual test with 15% to spare!
Good luck, and hurry! The NEW PMP exam will be out around September and most of the existing teaching materials will require updates.
D.E.R. Management - IT Project Management Consulting