I am pleasantly surprised by how effectively these curler rods curl my hair. I prefer curling my hair without heat, minimizing damage to my fragile hair. These rods create bouncy and long lasting curls. I recommend applying mousse to damp hair and putting in the rollers while hair is still damp, not wet. The mousse helps hold the curl without causing stiffness. I leave these curlers in overnight, although they can be used during the day. I feel that I would not achieve long lasting curls if I left these rollers in for only a few hours. They are not that uncomfortable to sleep in, especially if you ensure that there are no rods pulling on the hair at the roots. These curler rods are very affordable and they curl my hair beautifully. I highly recommend them!