In reality, this is somewhere between 3 and 4 stars for me.
It definitely provided some insight into a Buddhist mindset, so in that way I got out of it what I was looking for. And it certainly has much practical advice that one can apply to cultivate patience and discourage anger in oneself, regardless of one’s spiritual beliefs in a short text.
That said, I think I’d like it more if I were already Buddhist. I’m left wondering how strong the arguments would still be if you didn’t believe in karma or reincarnation, which the author takes as a given. And the writing, while clear, is a bit dull to follow.
Overall, I’d recommend it to somebody who wants to know more about Buddhism (note: Geshe Kelsang Gyatso has a ton of other books for this purpose as well), but if you’re just interested in some practical life advice, maybe learn to meditate with The Mind Illuminated instead.
P.S. If you do read it and don’t know much about Buddhism, I recommend starting with the appendices.