It's a 3,7/5 rating for me
Let's start by saying that this book has been of tremendous help in prepping my graduate exams in economics, and in general it is a resource that you should keep with you in any advanced economics courses. The best feature is for sure the extensive coverage of all the mathematics you need for a graduate econ program. It packs a ton of math, from calc I to (elementary) analysis, with a satisfactory coverage of both linear algebra and differential equations. Of course static and dynamic optimization are included and probabily they are the best part of the book. The rest of course is valuable but probabily you will be better thought somewhere else. The explanations in general are kind of soulless. Intuition is provided at the bare minimum and examples are not many. Also concept are immediatly presented in their general form, which can be disorienting sometimes. All of this added with the fact that exercises are very few tells me that this is perfectly suited as a reference book rather than for self study. Also the organization is sometimes odd. For example linear algebra is not entirerly packed in one part, but it is divided in 3 sections separated by 200 pages from one and onother by other topics, which is kind of odd, and also the optimization is structured in a way such that all the types of optimization problems are presented twice, once analyzing only the FOC and then only the SOC, which at least for me, is kind of weird. And finally some parts (especially the ones contained in the appendix) are just useless in the way are presented. For example the section "introduction to probability" is just a list of facts and result of basic probability theory packed in like 3 pages, so completely useless. So, to conclude, i think that Simon and Blume's is a very helpful resource for any grad student but it is not vital. The best option is probably to buy a calc, linear algebra and a basic real analysis book and focus on the topics which are more important for economists, the choice is very broad and the explanations are for sure better laid out, this accompanied with Sundaram's book will get the job done.