They work great on CAT6 Cable. Very fast and easy to terminate cable runs using these while standing on a ladder compared to conventional RJ45's I have used. (NOTE: I used two on a CAT5e Cable and had two open wires which required re-crimping)
I purchased these based on the good reviews and I made a few cables with them this weekend. I had no problems at all, they seem perfect to me. All my computers and devices connected by wire with these ends are listed as gigabit connection on my local network. What more could I ask for?