My favorite FPS is probably Metro 2033/lastlight. The game is just flat out amazing, especially in terms of graphical design.
COD and Battlefield are decent.
In terms of call of duty, i only care about the treyarch ones, since they are better, they try to do something different, rather than the boring games from infinityward and sledgehammer. Im not hyped about advanced warfare at all, since its from sledgehammer and they usually dont think outside the box, they are not known for innovation, rather the opposite.
In terms of Battlefield, i mean what is there to say? its a fun game, BF4 was rushed a bit too much causing a lot of day one problems.
I feel like a lot of people dont take other shooters into account other than, Battlefield, COD or Halo, which is a real shame