I am very happy with how the wire stripping machine works. We have run quite a bit of wire through it and so far no problems. It takes a bit to understand the settings on your depth, but once you master that it is a breeze.
This is a hand saver. Ive been scraping copper wire for years, and im pretty good with a knife. But after a little practice this thing works pretty great. No more cuts to my leg or hands.