I read a book I like and usually like other books by the same author. My favorite Puzo book is The Godfather, but I still enjoyed almost all of his others. I could never get going with the Fortunate Pilgim. The Sicilian is a great book, made better by the fact that there it is based on a real person. Omerta, The Last Don, and the Fourth K were all good reads, but not on a level as the first 2 (in my opinion). I haven't tried The Family yet.

By the way, my 18 year old son read The Godfather and loved it. He asked me what book to read next and I suggested The Last Don because it seemed to be more similar in pot to the Godfather. He didn't care for it, but loved the Sicilian. That gives you two opinions - one from a young guy and one from an old guy like me.