<p>which prep book (barron's, CB, PR, sparknotes, etc) has practice tests that are very similar in difficulty to the real test?</p>
<p>Past real tests have the highest correlation in difficulty to future tests, so CB.</p>
<p>I agree, although it would be really nice to see the CB update the math study guide, which has a 2002 test and a 1997 test: getting a bit old. Surely they can release another test or two by now…</p>
<p>kaplan and sparknotes were really helpful for me. princeton review was alright (seemed a bit different from tests) and barron’s just wasn’t really worth the effort. i didn’t get an 800 a single time i took a practice test, but i got an 800 on the actual thing.</p>