Right now I am using a Duel Gundam Assault Shroud and have OC5 with all points in attack. Red Critical hits take out huge chunks of health. I can 2 hit kill a Shining Gundam.
I want to know what the most powerfull sniper unit is. DPS is really what I'm looking for, so factor in reload speed reducing skills. Also, does the sniper precision skill part stack with the skill to make always red criticals? I doubt it would.