I had the Yellow Smiley Face Viz-A-Ball, if I remember right they originally said you could sand it 4-5 times before the picture stated coming off.
Now mine didn't get beat up, I just had to remove the track. So I didn't go lower than a 400-600 wet/dry paper.
I got at least the 4-5 sanding on it before I started seeing white areas around the holes first. The picture did get a faded look as it went along.
here's what it looked like around when I retired it.