I like a power sharpener, but it can;t be a standard wheel like the Tormek, which rotates in a vertical plane. I use a water cooled Woodtek unit ( approx. $100) which rotates in a horizontal plane. It came with a 1000 grit wheel, and quickly sharpens my chisels. It is easy to see what you are doing. Woodtek also sells a 400 grit wheel, but I don;t think I need to grind away that much steel. There is another unit available from a different manufacturer , which uses glass onto which one sticks sandpaper, but I haven;t used it.Then I use a buffer on a slow speed grinder. The buffer is just a few thicknesses of cereal box cardboard glued together, then charged with green rouge. I have a couple different cardboard wheels, of different thicknesses, depending on the chisel to be buffed.
Mark