I used to use mine, but bought the Ultrex this year and never pulled them out.
Mine are very old. They're the round style. They would unwind in the wind. I fixed that problem by drilling holes in each one and added a 1/8oz worm (cone) sinker. I made the hole just big enough so the sinker wouldn't go all the way through. I super glued the sinker in place and then used some Goop to waterproof it. Now when it drops, the sinkers hold it in place. Just make sure to place your sinkers on the same side. You want both of them to be pointing down when they come to rest.
They can be made with some pool noodles and pvc pipe. My dad made some like this and they work fine. They do sit low in the water.