My succesfull experience
I'd like to share with those people struggling to get their PMP certifications my experience:
First: Don't give up! It's worth every minute of sacrifice and hard work. That's the point of getting such a certification, it will get you out of the crowd.
Books: I don't recommend anyone reading the PMBoK from cover to cover. It's a manual, a reference guide, and should be used like that. Stick to one book and use others (PMBoK included) to skimm through the subject.
Kim Heldman: My first book. It will make you understand how pieces are put together, cause it follows a project life cycle order, not knowledge areas order. And this will make a BIG difference at the exam.
Rita's book: My main book. After getting a great understanding of how things fit together, I studied Rita's book, than the correspondent part at Heldman and lastly at PMBoK.
A VERY GOOD AND USEFULL TIP: Build a mind map as you progress through your studies. It will help you a LOT to stick things to your brain and facilitate to revise later. I recommend FreeMind (it's free and very good). If anyone feel interested I can provide mine (email me at firstname.lastname@example.org), but the point is really BUILDING it (like a WBS).
I also bought Rita's Hot Topics (paper). Good for quickly revising topics when I was at my reading room (bathroom) or somewhere like a waiting room.
Took a look at HeadFirst but I didn't like the style. Funny pictures and jokes made me deviate a lot, so I droped it.
Tests: PMFasTrack (by far the most close question to the actual exam), Heldman's (came with the book), Oliver's (it will make you search for subjects that may be on the exam. Not as detailed, but answering the question will make understand concepts).
Also took HeadFirst, but they are TOO easy. Good for a warm up, but don't get close to the exam.
PMZilla: Pointless. Very focused on remembering PMBOK's every line and word (read Mento's post about it).
I would stick to Rita's, made me score a lot of questions right.
I would strongly recommend you memorize ITTO, but knowing exactly WHAT they are and how they fit into the whole. The exam asks a lot of questions about them but DESCRIBE ITTO instead of saying the exact name (specially for TT). So you MUST understand the whole picture.
Formulas: You must know them and be able to use with folded eyes (eat them with beans, as we say here in Brazil). The exam you give you a lot of information for you to use the formulas backwards (like giving you CPI and AC and asking for EV). Don't expect too many questions with calculations (less than 5 in mine, and pretty easy).
The exam is tough. Tougher than any simulate questions I had. But if you are prepared and understand the concept you're going to score well.
Practice as much as you can. Feed your mind map and revisit it periodically. It you save your ass in several questions.
Almost all questions are situational, and have a problem hidden behind an apparently other problem. Rita's questions are pretty good at this point. Almost all have 2 answeres very close to each other. Lots of BEST, FIRST, NEXT type of questions.
Read the Code of Ethics and Professional Conduct. A lot of books reference the subject when they were separated, and a few changes happened (at January 2007)
Even if you study like 36 hours a day (at least it will look like), you WILL face questions you won't have an idea where the hell they took it from. So relax!
Use your entire time (you paid for the whole package and won't have any discount for leaving early). Answer all the questions first time and take a break. Drink a cup of watter, take a deep breath, relax and eturn to revise everything. You WILL find missed points and worng answers.
Make your study time fun, think of it as an investment. Thing you will have good stories to tell your friends about how hard it was and how happy you are now (hitting the last stage at Maslow Hierarquy, ha!)
Spend the money you have to spend. Think as an investment, not an expense. Don't listen to people telling you how exaclty you must do or how dumb you are if you spend money in this or that. Listen to several opnions and make your own. You have to act the way that make you confident. It's YOUR way, YOUR professional life. Thinking this way will help you to improve always in you professional and personal life.
PS: After you click that "end exam" button, you will face a blank screen for a few seconds. Your heart will try to jump of your chest. Than, after that hard moments, a screen will happen with what? A satisfaction quiz about how happy you are with the test center (9 questions I guess). I almost died in my chair. Than, after answering patiently every one of them (after all, what is 9 questions after 200 answers and 200 revisions and I don't know how much changing answers), a few more blank screen seconds and there you are: Congratulations and welcome to PMI. Now you are a certified PMP (or something like that, I was not able to read anything else after "Congrat...")
Enjoy your experience and celebrate your win. This is what makes life fun!
Robledo Castro, MSc, PMP