No one knows yet because no one's taken the new test (just AAMC's* one practice test unless they've added more). Here's what I can say:
1. The best way to use EK, IMO, has been to attempt to master everything in their lesson books. Since their books are the most concise, you will occasionally want more explanation for something. When you do, that's when to use the internet or look that particular topic up in a more detailed book. The great thing about EK is that you don't have to suffer long explanations of stuff you already know. That frees up time that you can use WHERE YOU need it. (My EK Instructions: Use the EK lesson books and go in the order the chapters are presented. Work as fast as you can. If you make a study schedule, keep in mind that some topics may be much faster and easier than anticipated, and others just the opposite. Consider forging ahead if you finish early on any day. Do NOT touch the EK 1001 Questions book unless you truly need the practice. If you encounter a topic in the EK lesson books that isn't adequately explained go to another source such as another MCAT book, the internet, or a tutor. Careful NOT to waste time on subjects, and continuations of subjects, that are beyond the MCAT. Prioritize learning and mastering exactly the topics and SCOPE that is presented in EK.)
2. I also bought EK's psych and soc book, and so far it seems easy (knock on wood)! I'm going to prioritize learning all of the vocabulary in that book and all of the topics in that book. Once I seem to have it down, I'm going to do a quick review of everything else and take AAMC's one practice test. That should be revealing, in terms of whether or not EK psych/soc is enough. Note: I'm going to attempt to master the material in the book, NOT just read it and do the questions. IF EK IS NOT ENOUGH, my thinking is that EK will probably at least contain the most high yield topics. So it would still make sense, to me, to learn it first, and IF it's not enough, it will make my next book a quick read. (At first, a lot of the definitions and concepts in this book seemed like common sense to me, but my sense is that AAMC will find a way to be tricky and test our understanding of the definitions and limits of these concepts and theories. I think we'll have to know them very well. A psychology or sociology student might have some clue about how these questions will be made tricky.)
*In the past, in my experience, AAMC practice tests have been the best indicators of a person's real MCAT score. This is possibly because AAMC used retired MCAT questions from past real MCAT exams to make their practice tests.