They are called "roof jugs," after all. That in mind, I feel like my review is a bit limited since I have used them exclusively on a 45 deg wall. At 45, they are still very, very, very positive. The exterior is very unique and beautiful; the interior (where the fingers touch) is basic bucket without a unique feel). These jugs would still be positive at 70 deg. When you throw to these holds on a 45, your hand grabs them from a different angle than you would is approaching them on a steeper wall. One of the holds can be a bit sharp on dynos from 45; that wouldn't be an issue on true roofs. Atomik has many great options for 45 deg walls; however, this set would not be my first choice at that angel. If I ever build a 70 deg wall, I'm sure they will excel there.
TL;DR. Likely best on 70 deg to horizontal. Not my fav at 45 deg.