I think this is the first Carl Sagan I've ever read cover to cover. I have owned Cosmos but never read it.
Anyway, if you've seen the film, it's actually a lot like it. They compress various characters into one (in the film) and in the end (in the book) 5 people are sent in the machine, rather than just Dr. Arroway (the person played by Jodie Foster in the film).
But it was also a lot more fleshed out in the book - there is a lot of scientific, philosophical and religious meandering in the book (possibly biased towards the way I view the world, so mileage may vary on the enjoyment). As well, there some Cold War tensions about to add some interesting political dimensions (which I don't remember being in the film).
It's quite enjoyable in the sense that it covers broad themes, like the limits of evidence, skepticism, the intersections of science and politics, loss, love, grief and family. It's quite a subtle but heady mix of things.
Also, it passes the test in glorious technicolour. It even gets one of the bonus points in that there's a subtle criticism of male dominance in scientific professions. Also Ellie Arroway don't take no shit. It's lovely. It's the book I'd want young women and men to read - I mean, the president of the United States is a woman in it! Amazing!
It even has diversity! The five people who go into the Machine are 3 men (Russian, Nigerian and Chinese), 2 women (American and Indian). Part of the plot takes part in Japan as well as the United States. There's a lot of talk about humanity being one, seeing the best of all cultures. It's delightful in it's lack of stereotyping different people.
Anyway, I think it's lovely. It was a soothing balm of coming to terms with many things, the innate love of scientific discovery, the hard work that comes in the face of discovery, tenancity and just many GOOD things. Things you want people to read about and admire about science and curiosity.
I think some people could be annoyed by the ending - if you read it one way, it's kind of like equating that some times you need to take things on faith. But I don't think that's the central message - it's to keep searching for evidence even in the face of overwhelming odds.
I highly recommend this book, it's definitely a 5/5 stars from me. It's definitely going to be one of the top five of this list!