I love SleepSounds! I have been using it when needed for the past two years or so, and it’s always extremely helpful. I don’t have premium, but I find default to be enough for me, especially because I mostly use the raindrop sound effect. If you routinely have troubles with sleep, then maybe you should get premium, or if you are a person who likes extensions. So far as I can tell, leaving it on all night doesn’t use much more than about 3%, but this could definitely vary. The user-friendliness of SleepSounds is very good, and the sounds themselves (rain, waves, wind, rainforest, fire, message, and lullaby) are also extremely appealing, at least to me. Again, I love SleepSounds and suggest it to everyone, no matter how successful (or poor) their sleep schedule is.