So I finished F.E.A.R. 2 last night, and I'm glad I did. The ending was sufficiently weird enough that I'd be interested to see what else they could do with that world if they really wanted to go off the deep end, but at the same time it was enough of an ending that I didn't feel like I had just finished part two of a trilogy. 
Going back a bit, I was roughly half way through the game when I did my first post on it a few days ago, and enjoying it much more than I expected. 
Well, I did run into a bit of a flat part about a day and a half after that writing. There was a whole level where the enemies seemed really bullet-spongy, and the level itself didn't seem to serve any purpose other than to introduce a new weapon, and stretch the game out. Not that it was badly designed, far from it, but it just felt like padding. 
Aside from that, the flow of the game felt pretty good: The levels made sense, there were only a couple of places where the enemies seemed infinite, and they didn't ever get stuck on the environment that I noticed. 
 
I think I got about 60 out of the 70 journal entry / story plot pickups; I don't know how much I missed from those last ten, but with what I got, the story stayed pretty interesting from start to finish. I think I got about half of the reflex injectors that give you the bullet time effect, but only near the very end of the game when it didn't really matter. For anyone playing the game fresh, I would suggest looking around for a guide on where to find those boosters; the effect made some of the fire fights a good deal more fun. 
It's also worth noting that the lead up to the final fight gave me a don't-wanna feeling. It was sort of like going into a haunted house, where part of your brain wants to not. do. this. but at the same time you have the feeling that it's something you need to do. And that was without any fighting, or sudden jump-scares. I don't want to oversell it, because Alma wasn't ever really a threat the other times she showed up, but everything that had happened during the game made that lead-up really effective. 
 
I didn't try the multiplayer, or download the dlc adventure, so I can't say anything about either of those. If you're not into rentals, I think it's well worth the 10 or 15 dollars that it's currently selling for used on Amazon.