I don't read a lot of biography, so it's difficult for me to judge how good this is in the grand spectrum of that genre. But this quick read certainly had things that I liked, and things I was disappointed with.
Things I liked: There was a birds eye view of Oscar Wilde's life, with a lot of details I didn't previously know; the appendix includes an extensive list of referenced works which indicates a depth of research I appreciate; the author provided a good argument for further reading, allowing me to make an educated decision about what other of the thousands of works on Oscar Wilde to dive into.
Things I was disappointed in: This biography definitely focused more on Oscar Wilde's sexuality than his works or philosophy. While I understand that his notoriety rose from his being a convicted homosexual, as well as an aesthete, that's not what I was curious about. What I was curious about, and why I picked this up in the first place, is that I have no context for his famous works- why he wrote them, when he wrote them, how he wrote them, etc. And these works get mentioned for a page or two, but the focus of every single chapter was on Wilde's love life.
My biggest takeaways weren't anything of Oscar Wilde's, but that Bosie (Lord Alfred Douglas) was a self-centered asshole of the worst degree, and Robbie Ross was a better friend than anyone deserves.
Overall, my expectations were disappointed, but I have to give this book full credit for being well-researched and giving the overview of a life that you can expect from such a tiny biography.