Having read the General Chemistry, Physics, and the majority of the Biology Kaplan books, I can say this: Kaplan sucks unless you are taking a course. The books don't really "teach" the material so much as "state" the material. I switched to TBR about 3-4 weeks ago, and let me say one thing: AMAZING. The General Chemistry and Physics books are so helpful. I never understood Acids and Bases, but I got an 11 (26/35) on Phase 1 of that chapter, and a 12 (22/27) on Phase 2 of that chapter. The passages at the end of the chapter really help to hone in on your weaknesses. They've enabled me to apply what I've learned right away to an MCAT style test, which helps me retain information better.
I haven't done Organic Chem, yet, as I haven't taken the class, so I can't speak to if it is good, but I have heard good things about TBR for that as well. Biology is a bit different, though. It is very detailed, which is great for me since I haven't taken an anatomy and physiology course. I am currently finished up the last chapter in Biology Book I (Physiology). I started out scoring 6's on the Phases, but that has steadily increased to 9's. This may sound like nothing, but for never having any experience in the subject, it's a marked improvement. What you must realize about TBR Biology is this: It's hard. Real hard. They go into so much more detail than is necessary, so if you don't want all of that detail, stick with EK or TPR.
I also own TPRH Science Workbook that you mentioned. I've only used it for a handful of passages, but the Biology passages are immensely more friendly than TBR. I did some Kidney passages after doing the chapter in TBR and scored 5/7; 6/7; and 7/7 on related passages in TPRH. Let's just say I didn't come close to that in TBR
If you want LOADS of difficult passages with very detailed information, get TBR. It has really helped me in PS. I have heard that your scores from TBR passages will generally go up by 1 point when you take AAMC practice tests. I started out hoping to get 10s in each section, but on Physics and Gen Chem I have been averaging an 11, so my goal is a 12. These books have really increased my confidence and information retention, and I'd definitely recommend them.
Now, I realize not everyone wants to go as in depth as I do and may have better recall from classes. If that's the case, I would buy EK books. They are brief, but they get the most important stuff covered. Then you can fill the gaps with a previous course book or something of the sort.
I would say definitely get some more verbal passage practice. I do three every day from either TBR, Kaplan (last one! Yay! they suck!), EK 101, and TRPH Verball workbook. It's nice to see a wide range of question types.
FINAL NOTE:
Materials are just materials. Ultimately it comes down to how well you use them. I have a friend who memorized the Kaplan books (and books only) from front to back. Seriously, he could recite almost word for word the pages. And he got a 32. I have another who used Kaplan with TPR and only scored a 26. You can do well with many different types of materials. You just need to find what works best for you.
Good luck!
