I took the exam last year. After reviewing the preparation booklet that QAI sent me, the only review that I did was to look over the book to get familiar with any terms that I was not familiar with. My 8+ years experience prepared me well for the material covered in the exam. I passed the exam with relative ease. My suggestion would be to be very familiar with all the concepts in the test prep booklet. If there are any subjects/areas that you are not familiar with, then seek out books in those areas to read & review from.
I took the CSTE exam 2 years ago. I used my 7+ years experience plus their little study guide they send and I passed the exam. I did think that many of their questions had many possible answers and were kinda bogus. All in all, it's been a great resume booster.