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.
As a 1L, these case briefs have made my life significantly easier when it comes to figuring out if my own briefs are covering everything that is relevant to the cases. I wouldn't say these are absolutely necessary or will guarantee you an A, but they're definitely super helpful when you're trying to figure out if you're on the right track. Plus the analysis section of the case briefs help give you a concrete example of how you should go about analyzing cases.
This was very helpful when I was studying for my Torts final exam. I would recommend this book along side a hornbook. This will only help you understand the cases and law applied in them but it is not too in depth with each concept. Very basic, but still helpful.