Tier 4 POI is still good doable within a game day as solo stealth.
Stealth headshots kill most of the sleepers.
And when you want to play as group you maybe should think about mellee weapons too.
I am unsure how well the knockdown works on the demonic one, but when you can keep him down because 2 with blunt weapons and maybe one with slash for bleeding effect.
Not to speak about that you don't need to spend the next day to gather resources for ammo.
Stealth headshots kill most of the sleepers.
And when you want to play as group you maybe should think about mellee weapons too.
I am unsure how well the knockdown works on the demonic one, but when you can keep him down because 2 with blunt weapons and maybe one with slash for bleeding effect.
Not to speak about that you don't need to spend the next day to gather resources for ammo.