Sectoids are a non issue, they seem to prioritize reanimation in my game, which is essentially just them wasting a turn. I think a sectoid has only actually fired on my squad once in ten missions. I had a ranger get panicked, run up to full cover, shotgun a trooper in the face, then get fired on by a turret which missed him.
MEC troopers, on the other hand... they seem to like running right past my front units to lob grenades across the map onto my rooftop-mounted snipers.
Steam + PSN: PHJF