IF you're aiming to do missions then avoid no lock as the NPC's have ridiculous accuracy, and make it a lot less enjoyable as they'll kill you faster than you kill them. Anywhere from traditional to partial free aim should be fine for missions along with free roam.
What aiming mode should GAFers play online? I'm afraid that all these aiming modes will fragment the audience.
Assisted Aim Full: Traditional locked on targeting
Assisted Aim Partial: Short lock-on period
Free Aim Assisted: Brief initial lock
Free Aim: No lock
The first patch for the next gen version will contain heists.
I thought heist were coming in the near content patch?