Review (1/5): OUCH!
Well in spite of some of the poor reviews, I bought this foil and cutter for my 8781 razor. Yesterday I spent nearly an hour using a styptic pencil to stop the bleeding from a cut from the new installation.
After further inspection, I determined that this foil and cutter would sometimes pop up out of its mount, exposing one edge end of the foil, which is quite sharp. As long as the foil and cutter stayed in place, it functioned correctly. I cleaned the socket carefully, reassembled, and have had no further problems. It is not as good as the original foil and cutter set, but it is working.