I have used it. I have used both the Zig 2 way glue pen and Tombo Mono Multi liquid glue.
I generally pile the stuff on to the area thick, push it down with my finger and let it set for a just a little bit and then either dust or tap off the extra on to a separate piece of paper.
The pink flags and some of the pink stripes on the big circles are covered with flocking, though its hard to see in this picture.
I think its so cute on cards. Janessa made one of my kids a b-day card with an Elephant on it and she did the ears with flocking and it was just so cute!