I don't believe there's a difference between the review books (could be wrong though, I never used them). When people on here talk about TPRH, they're referring to the verbal and science workbooks which are only available to people signed up in TPR's courses, or second-hand on eBay, craigslist, etc. and typically fetch $100+ each. They're worth it though. You won't find better verbal or bio practice anywhere else. In addition, the orgo, gen chem, and physics passages and discretes are second only to TBR's stuff.