This was the first Star Wars book I read and I liked it a lot. Since then, I have read about 6 more, but this remains the book that I can recommend the most, and that says something about its quality.

The character of Darth Plagueis was very interesting, mysterious, and powerful, and his teachings and interactions with Palpatine were very intriguing. I also liked the political intrigue (warning for people who didn't like this part in the prequels!) and the underworld dealings, but at some points, it dragged a bit. I like how it adds to the story of the movies without annoying contradictions or alternative events, and how it shows us the depth of the conspiracy and the power of the Sith under the nose of the Republic and the Jedi.

Another small complaint would be the significant shift in focus to Palpatine after about halfway through, and while it was also very interesting, it left our main protagonist a bit in the shadow in his own book.

Overall, an important additional story for the Star Wars universe and an enjoyable and easy read.