So I love Lord of the Rings, the Silmarillion, Martian Chronicles (and other Ray Bradbury books), Ursula K Le Guin(Earthsea), Kurt Vonnegut (Cat's Cradle, Sirens of Titan, Slaughterhouse Five etc), Dune, Game of Thrones series, Neuromancer, Asimov (basically everything but especially Foundation series), Terry Pratchett, and so on...
And I consider Gene Wolfe's work to be on a par with all of the above, and I would say he takes sci-fi to another realm. The Book of The New Sun is the first sci-fi series I read where I thought, "this is literature," as in, comparable with books by Dostoyevsky and Hemingway, and I don't believe this is hyperbole, it's just that good.
The other amazing thing about The Book of The New Sun is that each time you read it you realize you missed about 100 things in the previous read-throughs, there is so much "hidden" in plain sight and the subsequent read-throughs are like reading a completely different book.
So just read it please.
Edited to include Le Guin as another example of "genre fiction" as literature.