Finally got around to trying an Arko Shave stick, was a giveaway from someone I bought something from. I tried to melt it onto a bowl, does not really work all that well.
use a cheese grater and then mush all the gratings into the bowl
Arko is a tallow based soap. So it's not a member of the melt-and-pour glycerin brigade. That's why it didn't melt. The sticks are soft enough that you should be able to squash it into a container easily enough if you choose to do so. Personally, I think it's fine as a shaving stick but as always YMMV.