The trouble with short stories is that they do not have time to develop characters etc in the space available. This one works as the author has limited it to two characters it is a fairly simple story but ends with a twist that I did not see coming. I suppose the moral of this story is to read your contract carefully.
Good, unexpected end, but very unrealistic background. I liked the imaginative concept of retaining a SafeGuard for a moon. Much shorter than I expected though. I am having a lot of difficulty in relating a word count to a reading length, I'm too used to paper books I suppose, where you can do a guesstimate judging by the thickness.
Cost of 77p seemed valid for the length. I'd previously read the author's Kinesis book, which I would also recommend for a 4* read. (It would be better for spelling and punctuation improvements; not awful, but not perfect.)