I saw the tv series and thought about reading the book,
but I haven't got around to it yet. I'm certain it's an enjoyable read, but when a book becomes a classic, then it's joining this elite group of books is not nebulous or ambiguous. It never goes out of print and is taught in universities. Perhaps Lonesome Dove will join the pantheon of classics, but I doubt it. There are many writers of the west which were great writers: Zane Grey for an older writer and Cormack McCarthy for a newer one. But of all the western writers, only one comes to mind as creating a classic novel: Owen Wister with The Virginian. It is extremely difficult for a writer in this genre to appeal to and be selected by academicians.
For a novel to become a classic, two things must happen.
It must stay in print and it must be taught in American literature classes so a new generation of lit professors are exposed to the work. Those who read Owen Wister's The Virginian and Mitchell's Gone with the Wind, felt these two would become classics. Now no one reads Wister's novel and, to my knowledge, GWTW is not taught in lit classes. While Lonesome Dove may be a good book, I don't think it will ever attain the status of "a classic". It just doen't have the universal appeal of The Great Gatsby and The Sun also Rises.
The whole world doesn't live in Texas.