Two already this afternoon that have ruled out goals for Burnley and Sheff Utd, both by mm's (and for the Burnley one they appear to have drawn the line after the ball was kicked, not as it was kicked).
Linesmen have not made clear and obvious errors by not giving them, so I don't think VAR should scrutinise at all, just glance that linesmen have not made a glaring mistake and then let the goal stand.