TPR's MCAT 2015 review books have one 40-page chapter on biochem, and it doesn't go much deeper than what was covered in my intro bio + ochem courses. Assuming that the prep materials align reasonably well with the test content, I'd be surprised if it's necessary to take a full biochem course before the MCAT as long as you're prepared to do a little extra self-studying. But obviously the extra background wouldn't hurt (and there are many good reasons to take biochem aside from the MCAT).
I went to Barnes & Nobles and saw the TPR Biochem&Bio book, and IMO, I don't think it's sufficient at all. Looking at the preview 2015 test from TPR, it has a lot of biochem terms that you need to know. I haven't looked at the official test from AAMC yet, so I can't comment on that. (But I also looked through the preview guide's sample questions released by AAMC and there were topics in there that were covered in my Biochem class and not in my intro bio class - amino acid derivatives, SDS, specific questions about amino acids and lipids, etc.)
If you want to get a Biochem book, the best option for now would be Kaplan's & maybe a college textbook.
Some of the topics on AAMC in regards to Biochem go through a lot of Biochem 2 stuff, like glycolysis/gluconeogenesis/lipid metabolism/all of the pathways' regulation - which IMO, was not adequately covered in the ONE chapter in TPR. The cell molec bio stuff did look decent, though, and I thought that part was much better than Kaplan's. Also, they were really lazy with the practice passages at the end of each chapter. The new MCAT is changing in the way it's presenting the passages and questions, and TPR pretty much kept all of the practice passages in the old book + threw in 2 of the Biochemistry passages from TPRH workbook (these were really basic, too)- which weren't sufficient to cover the amount of depth needed for the new MCAT.
For Psych/Sociol, I would go with TPR. Kaplan looked a bit skimpy. TPR also came with 2 practice passages at the end of each chapter for psych/sociol, unlike Kaplan's.
Keep in mind that OChem is also changing, and TPR took out a bunch of chapters from the old MCAT's ochem book, and added in some addition reactions & experiments that you need to know. I would get their Ochem book, too.
Verbal (CARS) is the same. (Except natural sciences passages are taken out, so just skip those when you're practicing.)
Physics remains mainly the same, but they took out two chapters (momentum & solids). There were some topics that TPR left in their books that weren't on the new AAMC outline. Again, passages at the end of the chapter remained the same and do not reflect the type of passages that you will see on the new MCAT (more biologically-based, rather than pure physics/chem).
Majority of Chem topics will be the same, so the content review books for those will suffice, but "good" passages are lacking.
