Superb
What I will say is as a man with a busy family and work I don't spend an awful amount of time playing games but this one I made time for and felt compelled to get to the end of the campaign.
The Game play is very smooth and you feel like you are playing and not just there to watch. As you go through the game you will come across a wide range of enemies or big monsters who provide a good but not to difficult challenge which I found kept me coming back each night.
The levels do have a certain linear feel at times but then something happens at just the right point to keep things interesting.
Overall a very good game with a great story, but do play the series from the start as it is a good story and it really makes you feel part of it.