This book provides as much information as you could possibly expect in 100 pages. The author writes concisely and keeps his focus on the subject. He is clearly well versed in the history and politics of the region and can draw on his knowledge to set events in their proper context. This book is not just Castro's life, but because he held so much power for such a long time, it is also a concise history of Communist Cuba up to the end of the 1990s.
Another plus of the book is that Foss is able to write with as much objectivity as one can expect in a book about history and politics. Cuba is a subject that is all too often politicized and it is difficult to find detached, neutral point of view analyses. This is it.
Because of its size (excellent for carrying on a trip to Cuba, and perhaps donate it to a Cuban reader) this can not be an exhaustive study. But it is a good introduction to the neofite, and good summary and review for the expert. A bibliography at the end provides suggestions for further reading. Highly recommended.