Review (4/5): Look up how to use these beforehand!
I've only tried this once when my hair was wet and I had it in for several hours and my hair didn't dry while in it so the curl really didn't work. It didn't come with directions so I didn't know what I was doing exactly. Hey later looked up that you can do it with slightly damp hair and that will help hold the curl. There's no way I could ever sleep in these things but if I was going to be around the house all day and knew I was going out somewhere that night and had the forethought to use these in the morning then I would be very curious to see how they turned out. I imagine that with adequate time they really would work well!