Very good game.
Very relaxing once you get over the initial oxygen anxiety :)
Just needs some minor tweaks which I assume will be done in later updates.
1. There should be an option to "save as" rather than just overwrite your currently active save, so you can have a chance of not making unreversible mistakes, by loading another save from before you made it.
2. Placement needs a little work as it's possible to ruin what you've done by placing something that overlaps another, which cannot be reversed ... related to point 1
Other than that, don't hesitate, get it bought and played :)