Not a bad story, not great either. But it was entertaining. As with most older science fiction stories, it is dated. The technology described throughout the story is now contained in the palm of your hand. I like the fact that it is a stand alone robot story. While it is not Asimov by any means, we do see some original characters in Delta and Omicron. Both are described as th pinnacle of engineering in some long forgotten galactic war that happens to crash land on Earth. I liked it. I liked it enough to search for other books by the same author, and that's saying something.