I used the same book back in the day, no idea what edition it was. Probably 2nd as I took the test around the same time DLeg did.
It's a good test prep tool for the most part. My only gripe is that they glossed over some of the steps in the solutions, so you couldn't always figure where you went wrong. Also, it made some assumptions that left things too much up to interpretation that you would never see on the real exam.
I recall one question about I&I. The problem did not give a rate. I looked in my state's WW manual and took their value. My method was correct, but I got the wrong answer because the author assumed something different. Hardly mattered, because I attacked the problem the right way, but still frustrated.
Still well worth using as a test prep aid.