I don't know what scoundrels / operatives some of you guys have been going up against but I can assure you they had no clue what they were doing. I finish snipers / slingers with over 60 percent health normally, depending on whether hunker down was on CD and whether I cleansed sab charge in time.
Snipers / slingers have amazing damage and great utility, but nothing they do changes the fact that you can move 2m and force them to either:
A. move, negating hunker down and exposing them to leaps for a few seconds OR
B. Sit there and do no damage.