Didn't buy one but I made one with a piece of coat handger and rubber tubing. I also made that auto hook setter rod holder that Cabelas sells. Do you remeber the auto hook setter tip up that bass pro sells for ice fishing, made one. As you can see all these gimics can be made with house hold items.
Back on topic, my version of the tail dancer works as good, if not better than the original. Yes, it actually works but when you set the hook, you got to quickly remove the line from the gizmo, or else you will get crazy line tangles. oh, ya, only works with spinning reels, but not spincast or bait casters.