Don't worry too much about the PV. By the point you take it, you are fully prepared and will have seen everything that it is going to throw at you. It is a slow problem for the most part. Study while in OKC as much as you feel like you need to and you will be fine. Nerves are going to be your biggest threat on PV day. Learn how to control them and if you are someone who gets nervous easily, hope you don't get an afternoon time slot like I did.
Hope this helps a little. I just took it on Monday. PM me if you have any other questions about anything.