I haven’t used the Arc Time brand, but am very fond on the Tri-Mix made by Diamond Ground. Don’t know how similar it is but same deal on the cost. They claim it’s a Top Secrete and proprietary compound.
I’ve used it on Ac and Dc and think it holds a point better than Lanthanated.
I have noticed though, that something in the mix seems to migrate to the tip after a while and forms a small cobalt blue ball on the tip. It has less a tendency to form that dark grey oxide layer that the 2% Lanthanated does.
Overall I like it allot.