The core story premise of Burnout is a classic one, having been told many times over the last few decades. Unfortunately I didn't find Burnout to be a satisfying read.
I could make no emotional connection with the characters. They were thin on substance, and static over the course of the book. I was never surprised by a characters' actions. What suspense existed was driven by what happened to them and not so much by their choices and actions. Some of the devices used to share information about a character were rather annoying. For example, more than once a main characters explains in first person what experience in their background allows them to accomplish some task.
The skeleton of the story line was interesting, and the NASA ops and historical references were fun. The reader is 'dropped' into the story and has to get their bearing along the way as do the protagonists, "murder mystery" style, which I personally find an appealing approach. But the story and its novelty just weren't strong enough to "make up" the difference. The sci-fi genre is notorious for books arguably weak on character development that are still enjoyable reads because of an interesting story line. But the funny thing is, such tales end up adding "character" to the characters, even if only by some form of literary osmosis. Burnout doesn't really deliver in this regard.
One final point are the two completely gratuitous sex scenes. They aren't important to the story line, and don't add insight into the involved characters or their relationships. One of the scenes had potential, as it seemed to be setting up for a sub-plot questioning the nature of the relationship of the couple. Sadly, this was not to be.