In humid climates, tape actually sticks better than the paper. Just need to carefully allign, smooth on firmly and overlap strips.
As for strength, it's a little weak in big peices fully nekkid, but good in small or laminated peices.
Biggest downside of bare dt foam is it's low tolerance for abrasion. It'll gash if you just look at wrong. A layer of tape/contact paper/glued coffee filters/polyurethaned glass cloth will help with that. One side is ok for a wall, but make sure every exposed side is covered with something.