I am taking PMP exam this weekend and I have been studying, re reading, and taking practice exams.  

I have taken the following Practice exams:

Head First (200) 82%

Exam Collection (200) 75%

Oliver Lehmann 68% (175)   

PM Study Free Exam (200Q) 72.5% 

Christopher Scordo(50)  90%

PMPExam Simuator/PMPrepcast  74%, 66%, 71%, 70%

PMZilla touch Questions (30) 57%  ;-(

PMstudy (4 Exam pack; 1st exam 3 more to go) 73%