The ECE exam is more difficult than the DSST exam. The reason is the scoring that ECE uses. There scores are not based on how many overall correct answers you have, rather, it is based on how well you do in each content area. You could do well on 2 content areas, fail the third, and as a result, fail the exam. ECE also will ask you more detailed questions, not all, but there are some were they delve more into the weeds, to use an old expression.

I used a book by Stephen Robbins for this exam, Essentials of Organizational Behavior, 8th edition. It is 13 or so chapters, 280 total pages I believe. It is easy to read, and it is worth it! The one thing you do not want to do with ECE exams, is pay the $205 and fail the exam.