An epic story. A view of France after the French revolution. A great description of the battle of Waterloo.

You really have to be committed to finish this book. It's really really long. About 5 to 6 times the length of a "normal" book.

Victor Hugo's writing is quite easy to follow, almost like a casual talk.
As one of the most important pieces of literature, I think you have to read Les Miserables once in your lifetime.

That said, do not read the book if you expect it to be life changing. No deep philosophical ideas here. You will see the world exactly the same way you did before you read the novel.

It's a nice story with great character construction and several times steps away from the main story to give you a description of life in France (nobility, thieves, clerics, lower working class).

In summary: if you're looking for a novel mostly for entertainment purposes and can commit to long hours reading it, do it.
If your reading habits involve more philosophical, life changing revelations, maybe the long hours you'll spend in reading the Les Miserables would be better spent reading another book.