F.E.A.R. 3 can also be played in co-op, and often times I felt that is how it is supposed to be played -- some sections were quite challenging on the normal difficulty. Bringing Fettel's unique abilities to support the Point Man would have definitely made things easier (and maybe more entertaining as well).
The problem with playing a horror game in co-op is that it stops being scary. However, I think that making the game (jump) scary wasn't the main goal; scoring points is not something one can have and still retain a spooky atmosphere -- in my opinion anyway. Which one of the two endings you get, is in fact decided by which brother has the highest total score. (In singleplayer it is obviously the brother you are playing as.)
The game's script was co-written by comic book author and novelist Steve Niles (30 Days of Night) and the cinematics directed by John Carpenter. They are indeed quite cool. Although, maybe unintentionally comical as well; the Point Man still has no voice-acting and just keeps silently glaring at the talking Fettel in the third-person cutscenes. It gets quite hilarious.
A new gameplay mechanic is the first-person hard cover system that unfortunately felt quite clumsy to me. You do not really want to -- or cannot -- sit in cover for long anyway, though, as the enemies are quite eager to throw grenades at you. They also use the cover system themselves and often completely disappear behind a barrel or such. The health bar is now gone as well and only the oh-so-real bloody screen is left to inform you of your state.
Graphics and story-wise F.E.A.R. 3 is the strongest of the bunch but I think its gameplay is not quite as good. There is just something with the game's weapons. Like the previous game, does this one have multiplayer as well. Maybe someone still plays it; I do not care enough to try. I might replay the campaign as Fettel, though, as I am somewhat interested to see how it actually works.