QR was my absolute worst section on the OAT, primarily because of the time issue, but also because I was not exposed to certain types of long word problems before my first test. Before the first test I studied chad's videos and some of the Kaplan course for QR, and I scored 240.
I knew I had to do something different, so I bought the Math Destroyer. I went over the first 4 test not timed, just seeing what I could figure out. It was not pretty. So I would go over all the answers and work every problem out until I understood it. Then I took test 5-7 timed over the next few days. I also did the free DAT bootcamp QR test online. I still did not feel 100% confident going into the test, but I ended up making 50 points higher, a 290, on the QR section my second attempt. I think Math Destroyer is definitely the best to expose you to all types of problems, but don't get discouraged if there are a few you don't understand.