On Arc Force, Jody Collier has some good videos discussing it, and in this video he mentioned that for 7018 it is often recommended to use 30% to get a buttery type puddle. I will need to try it down that low.

In another video he is running the Arc Force at like 77% with some 7018, and even he says it seems to vary and there's a lot of variables. Seems to be a wide range of use, depending on what it needed.