I've just noticed that this is due to be published in the SF Masterworks series, wiith the original US paperback cover, even!
I read this about 20 years ago, not long after it came out in 1977, and again a couple of times since. Probably my favourite Pohl book. It's the story of a man named Robinette Broadhead, his struggle to survive and make it rich in a world where most people are poor. On an asteroid named Gateway, a long-gone species of aliens called the Heechee left a thousand of their spaceships. No one knows how they work, but it is possible to operate them, to go to preprogrammed destinations elsewhere in the galaxy. Sometimes the crew bring back valuable discoveries. Sometimes they come back dead, or not at all. It's also the story of Broadhead's guilt at letting something terrible happen to his girlfriend, Klara, and how he learns to deal with that.
What makes the story for me is a mixture of things - Pohl's use of sidebars to give us a picture of the world the story is set in, for instance. The sense of mystery created by the fact that no one really knows what they're doing with the Heechee ships. His telling of the story in the form of flashbacks interspersed with sessions with Broadhead's psychoanalyst (who is a computer programme). Even the way it ends so suddenly, in just a page or so, when the actions that Broadhead spends years regretting flash by in a blur...
Well worth anyone's money, I'd say, and certainly an appropriate addition to the SF Masterworks series.
If you enjoy this, go on & read the other Heechee books, such as Beyond the Blue Event Horizon & Heechee Rendezvous - Pohl has created a fascinating Universe to set these stories in!