This was a good read for the most part. The author "plays" with the technical aspect of space travel and living/working in space. The military aspect of the story was great. It was/is a pro Marines story, with all the associated flag-waving and hoopla involved. Character development was good as well, although the non-Marines characters were not as fleshed out as the Marines.
I would have like to have seen/read more about the scientific findings (no spoilers here) on Mars, which were in my view, crucial to the underpinnings of the story. The bones if you will.

Anyway if you like hard science, military and an interesting cast of characters, you should enjoy the read.

Sala Kahle.....