Amazon calculates a product's star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers and factors that establish reviewer trustworthiness.
If you have 2nd edition then there is no need to buy this one. Some "more" addition is not beneficial for exam point of view. You just need an idea of some topic in AnC. More and more material (in AnC) is just waste of time instead use your time in some other subject/topic or in other work. In anyway no one suggest particular book for AnC because it becomes useless in mains and in pre it just ok but not good/best.
Information overload! Although the whole book is relevant, the information is just too much. Questions asked in upsc are too few and unpredictable. Old handwritten notes would be better along with value addition from other sources like CCRT website.