The only actual test I used is the NCEES one. I suggest saving that until about a month before the test to help pinpoint where you need to improve. Other than that, I would just work the example problems in the references like HCM, and from what ever course you are taking. I was lucky enough to get notes from a friend that took Testmasters and I took School of PE. I worked every problem between those two items so many times I could tell tell you the page in the Greenbook the answer was on. I personally found 6 minutes solutions to be way more difficult than anything I saw in practice and on the test. With saying that, if you can solve those problems, you are in very good shape. I ended up just reading the problems and tabbing some of the pages with what I considered tricky solutions.