Montgolfier Winter by Alisdair Stuart is quite a bit longer than the recent fiction in Hub has been. The start is a little ropey, there are some clunky sentences and a couple of typos. I'm being picky - Hub has set itself high standards. However, the writing becomes more assured after a while and what follows is good. The story question is essentially - what else is there on this planet and what is the mad professor chasing after. The suspense is built up well and the reveal is handled excellently. The characters are a little two-dimensional but no more so than most plot-driven commercial fiction.
Perhaps the most frustrating thing is that I'd like to know more of the backstory. How did the characters come to be where they were? How is it that a church could buy a planet?