I have used the sandpaper on glass method, but have moved to water stones. The sand paper sharpened my plane blades very well, it just seemed that I went through many sheet of sand paper, it seemed more expensive in the long run that investing in some water stones and a flattening stone to keep the water stones flat. Also it was a pain unsticking the sand paper from the glass when it was time to replace it.

I have seen some of those spinning disk with abrasive type sharpeners coming way down in price, far less that a Tormeck machine. I am tempted to buy one and try it, but once again a am probably too cheap to keep buying abrasive disks for it.

Ken