A good solid entertaining FPS with some nice ideas.
It isn't particularily long, but it is just about long enough. The story isn't amazingly good, but it is pretty decent.
The combat is enjoyable and the mechanics work very well. There are a variety of ideas and methods involved which adds some variety. There are upgrades for weapons and abilities but ultimately they aren't very interesting and you will probably find yourself just running past the upgrade machine once you have gotten the upgrades you want and upgraded your two favourite guns power.
In the beginning it felt quite a bit like Bioshock, there were quite a few similarities in terms of feel and the way it went about telling the story. As time went on it felt more and more like Wolfenstein which isn't surprising as it is of course made by the same company. Wolfenstein was enjoyably mediocre, this game is better than that. Largely because of a more interesting story that is brought to life by for instance the cryptic messages you find written on the wall every once in a while. This was a nice touch as it meant you were always thinking about the plot and wondering whether someone was double crossing you etc etc.
Ultimately this game isn't groundbreaking or particularily spectacular. It is however an enjoyable and well put together FPS game which will give you 8 hours of entertainment (provided you read the notes, have a look around etc etc). I liked it.