I use these on a vertical wall, a 30 degree wall, a 50 degree wall and a ceiling. They are good for setting V0 - V2 on the vertical and 30 degree wall, and around V3 or so on the steeper 50 degree wall. They are quite difficult to hold on the ceiling, but could be a good addition to add to an existing route.
They seem to be a little more deeply incut than the round mini jugs which makes them slightly easier to hang onto. Overall, they're nothing fancy, but you're getting a lot of good holds for a good price.