Just received a razor from eebay. Inside is an odd looking old blade: it's a Safe-T-Guard Face Guard with some odd teeth-shaped ridges running along and over the two cutting edges. I'm guessing they were meant to limit the blade's contact with the skin, and dragging the edge lightly along my thumb does nothing whereas any other blade would draw blood. So I guess the safety feature does kind of work...but how good of a shave can did a blade like this give you?