Hi Warren,
I would strongly advise against going into the PMP exam without having done a good number of practice exams.
The PMP exam is quite lengthy and the exam0taking skill can be quite different from the process of learning. For instance, you could know the material really well, but you may not be in the right frame of mind to actually attempt the exam. That would be a shame to not do well on the exam even though you know your stuff, simply because you were not "prepared" enough from an exam-giving perspective.
You do NOT want to go in "blind" on this dimension.
Personally, I used the PM PrepCast exam simulator and found it invaluable in my preparation. The fact that you get used to the kind of questions that may be posed in the actual exam, get used to timing yourself, allowing enough time for reviews, and get real-time feedback on your progress and performance, is extremely valuable in preparing for the exam.
You could explore various options for test simulators, you don't have to take my word for it and stick to only PM Prepcast.
But please do not attempt the exam without ever taking any practice tests - that is too great a risk to take!
Best of luck!