I've got mine on ultra @1440p. Initially I put it on 1080p, but I was getting huge dips in frames when going from inside levels to outside. Like, 110FPS down to 30. I set it to 1440p, now it's like 80 inside and 40 outside. I would guess it's my low clocked CPU causing the anomaly.
Great game, and so much better than the first. The drone is the stuff of legend. It's just an absolute riot throwing it up in the air and then sending it around to bother people. It also acts as brilliant cover fire to stop them firing at you