I don't grow either plant but I know pothos is easily rooted in just about any medium, even water.
I think the philodendron is a little more complicated. I know there are others in this forum who grow (and root) both. Hopefully one of them will join this conversation and give you more guidance.
When I use sphagnum moss, I either use it in the long strands it comes in or chop it up and mix it with perlite.
