I saw the single post ones there at a store and they didn't seem to leave much room between earcups if the headphonesare sitting on the posts and the cans are of any size. Also one thing I noticed as well was that unless the backboard has a rather large spacer behind it the earcups will be hitting the wall.
Call me fussy I know. It was frustrating to go looking for stuff like this and hardly any of it was suitable that I found.
It's really too bad for me they look nice.
I saw someone in the DIY section ( headphone stands ) that made something similar to those only with longer posts. Looked good.