DBT needs high light and CO2 injection, and while I've seen it draped over hardscape, it's very much a rooted plant.
I like the way Christmas looks better than java. Moss will never again be added to my tank though. I take out a golf ball size compressed every month. I keep neglecting to remove it all so it finds a way to carpet across some section of my tank. It's one of those things that do better when neglected it seems. I thought I got rid of it before I left for 9 months. Came back to a couple softball sized pieces I donated to my lfs.