Review (5/5): For the price, these are great!
I spent FOREVER looking for a headband like these, but didn't want to throw down $20 for three Nike ones that I'd probably lose anyway.
These are great! I'm an adult, but have a small head (& BUT A BIG BRAIN). These fit me perfectly and only made my head start aching a little after 10 or so hours. The assortment of colors is great. The quality is whatever; wore one and it snapped suddenly and flew off into the dark abyss of the bar I was in. This was the first time I'd worn it. Funny/memorable, but kind of a bummer.
I've found they slip a tiny bit, but I can go about a normal day/pilates class and only need to put them back in place every 1-3 hours.
In short, I love them, they're cheap and cheap quality, but I figure I'll just buy a new package once or twice a year and be set.