In my other thread on choosing a precalculus book for review, I went off topic and into calculus books, and how there seem to be these 3 main categories of books universities and high schools use -> the 1000+page ones with tons of examples, very computational, new editions every other year, etc. (Thomas, Stewart, etc.), the "intermediate" ones which seem to balance things somewhat (Simmons, Lang, etc.), and the very theoretical/analysis ones (Apostol, Spivak, etc.). The idea then was, if a university is using one from the first category (Stewart, Thomas - 1000+page computational ones), you as a student have no choice. You can either use that and stick to it, or choose to supplement it with something. Why would you do the latter? Because later on, you might run into difficulties when taking more advanced courses that use textbooks that are more complex. And the Thomases and Stewarts don't prepare one well for that. For example, at one school I'm looking at, they use the Stewart calculus book for Calc I & II. There is no honors version track offered - everyone uses the same book for Calc I & II. But they do have an honors version track for Calc III & Linear Algebra, and they use this book: https://www.amazon.com/Calculus-Two-Nonlinear-Undergraduate-Mathematics/dp/0387973885 For the non-honors they continue with Stewart for Calc III and a more basic/applied book for Linear Algebra. So the strange thing is that if one decided to to the honors track, they would seem to be at a disadvantage in terms of preparation, unless as I was saying, they supplement Stewart with something. So the question is, why do universities do this? And what is the best way for a student to bridge that gap? How can one go from a Stewart to the Flanigan book and not be lost somewhat? Professors don't seem to offer any advice on this - I asked! They just say do the work, and you'll be fine. But that doesn't seem logical, or fair, or correct. So yeah, this is partly for myself, but a question that I'm sure I'm not alone in. Spivak as a supplement may be too much for a student on his own as a supplement. Lang is maybe the book they should have used if they did offered an honors course for Calc I & II, but they don't. The system is strange indeed!