After a little experimentation I'd say it works pretty damn well. I did have to put my drill in high-speed mode as normal speed didn't seem to be doing anything. I also had to tape the magnets to the drill bit to keep them from flying off. After I went around the TV a couple of times it appears the color is fixed on the bad side. I'll check again in a couple of hours to see if it reverted or not.
Digg.com has some great stuff, you should be reading it.