Kaplan Qbank?

For those of you who did the Kaplan review course, how well did their Qbank questions prepare you for the exam? I'm getting between 75-80% on the Qbanks, but seem like I can't get over the 80% mark. Is 80% on the Qbanks well enough prepared or what should I be striving for? Also can you do "too many" practice exams? What other ways are you guys studying other than flash cards/Qbank?