I have physical copies of these books. They are really well quality material, well layouted, and the content is similar to what is found at fs.blog website. All the "mental models" for thinking they include are kind of p*rn for this kind of stuff, but it is nearly impossible to apply these mental models consciously in real life, especially ad-hoc real life situation. There is no time to think each different mental model for every situation/task/problem/matter. The most effective thinking is the real-life "quick math/no BS" style of thinking, and the real superpower is if you have made your own expedition to the matter, because then you can just recall the stuff you need from your own brain quicker and better than any LLM.