I was hoping I could test these a bit last night before the special WOC, but we didn't get our free ones until 11, right before the show.
Things that haven't been discussed yet is they have an on/off switch, they are really heavy and required the use of bobby pins to stay on my head, and they have replaceable batteries inside (3 AAA). They cannot be embroidered because of the placement of electronics in the hat.
They are on sale several places in DCA (didn't look in DL) for $23.20 plus tax
The hats are actually adjustable. I pulled the strap through the connector (there's a hole) so you can string it through, and even with the strap strung through, it still connects together. I'm not sure if it was intended to be done this way, but it still works. Before I did it, the hat wouldn't even stay on my head.