I haven't had a full mount done yet but I've made my own european mounts and will definately have a full trophy mount done when I feel it is worth the money.
I would do it for the visual reference for memories rather than for bragging rights. (although I'd do a bit of that too I'm sure.)

Along with pictures, I also keep all of my old licenses and unfilled tags. Some day when I'm old and grayI'll make a scrapbook.