Creative Assembly made a masterpiece imo - I don't think there's a single aspect of the game that I consider to be anything less.
They have perfectly recreated the feel of the 70s film - the whole take on what space travel will look like, fits exactly as it did in the film Alien, and you can clearly see that they are lovers of the franchise; even a steam filled corridor can look amazing in this game; many of my in-game screen caps are just that - things that made me just stand and stare.
The story, though cliche, plays out at a great pace - you are never left feeling like you are trudging over the map for nothing - the progressive unlock of tools provides you a reason to go back to old areas; and the omnipresent Alien is there to provide you with a grounding to keep you running and gunning - again adding to the level of immersion and atmosphere.
Without spoiling it for anyone, I love how you get to play through one of the iconic parts of the first film - that really was an enjoyable diversion from Amanda's quest - I also really enjoyed the spacewalk bit; you really got to feel the claustrophobia of the space suit on that bit!
Hmmmmm, with the dark cold nights now drawing in - I might have to re-play this game for the umpteenth time now