I've OWNED one. And if any die ever deserved to be voted off the island, it's that one. The sodding thing was virtually spherical, HUGE (almost tennis-ball size), and tended to not stop rolling. Worse, when it did finally stop, even with a magnifying glass you couldn't tell what number it had stopped on half the time.
It was really only good for throwing at problem players, and its tendancy to break open and spill its little counterweight pellet fillings all over the place made it near useless even for that.
It was kind of a fun conversation piece, though.
Addendum: Now, how about d5s? I saw an ad for them once....