I had the same problem, no one around, except once.

Graphics were an issue, with alot of jittering, and i am running a sli 980 setup.  have not had this jitter graphics problem with any other game.

Grapple gun, ok, but if i use duel and shoot both, it should center.  

I dont like when grapple causes you to get stuck in the enviroment.

renders look good when it not jittery, but has promise.