All of the old sections are very good practice (especially the verbal, of course, but the others are worth doing as well). The way the AAMC asks the questions, the way they structure their wrong answers, etc. has changed very little. If you analyze the questions that you get correct as well as the ones that you miss - and focus on WHY you chose the wrong answer, not just why the correct answer is right - you'll be exposing yourself to a huge amount of valuable strategy that carries over to the new test.
Here's the thing, though - the "feel" of the passages has changed immensely, along with the huge shift to a bio focus. You'll find that the "old" AAMC passages are less experiment-based and less biological than the new test will be. As long as you don't expect it to be identical, though, it's still highly advisable to take the old practice tests.
