Other than Vinge, I don't have any familiarity with the others you mentioned. I'm a "hard SF" guy -- Heinlein, Forward, Niven, Pournelle, Joe Haldeman, stuff like that. I haven't kept up with the new writers. Oh, I'm really fond of Keith Laumer's time travel and alternate-universe stories.
Stephenson is well worth the investment. He falls towards the technological side of things. I recommend Snow Crash to every one I meet. And anyone interested in computers should be required to read his In the Beginning was the Command Line, if only up to the "MGBs, TANKS, AND BATMOBILES" analogy.
Dan Simmons is an amazing writer. I could not stop devouring his 4 books of Hyperion. Not really "hard" SF, but it is SF all right, and brilliantly written.
Stephenson is called one of the founders of what became known as cyberpunk with his Cryptonomicon & Snow Crash. But my real love is Diamond Age that explorers not very distant future with penetrating nanotechnology and societies transformed from today countries into a mixture of geographic countries and quasi-state entities uniting people who want to be united (like Free Republic). All this as a background to the primary theme of education, family, love and sacrifice.