I didn't have the Kaplan course, busy doing orientation for my job and moving to a new city. I did less than 200 questions from the Kaplan book and Saunder's (don't remember anything test day). On the Kaplan, both 180 question test I made in the 50%'s. I blame it on horsing around, never really sat down and really try to finish it in one go. I got freaked out by all the people doing thousands of questions on here, but it was too late for me to reschedule- still passed first time!
My best advice to you is to get that book from Lacharity. I was really surprised how many priority questions were on the test, and how random some of the questions were. Studying content didn't help me at all. I felt I always narrowed it down to two, and pretty much had to make my nursing judgment on which to pick.