Worth the wait and price. They performed as advertised. Charged them on day one and they maintained brightness all night. Easy to install and easy to change brightness and color.
The big question is how long will they last? I will be happy if they make it to 3 years.

I started by ordering one light and seeing how it performed in various locations (less sun to more sun) and to ensure I liked the color(s). After 2 weeks of testing I decided to order lights for the rest of the deck except the stairs that receive less than 6 hrs of sun (in April). On sunny days (in Apr-May so far) the lights will come on at dusk and last until dawn when set at the highest light settings. On a rainy day, they will shut off at some point during the middle of the night, but definitely last for the hours you'd want to use them. I have not experimented with setting the lights at lower settings, but I imagine you could set them a few levels lower and get longer output if that was truly important to you. They are definitely bright enough that you wouldn't really notice a big difference between a couple of levels of brightness. From a color perspective, the white setting still feels warm, so we've stuck with that. I am replacing existing post caps, so I'll plan to switch them in winter when I don't need the lights to help preserve the batteries. Installation was easy and I'm happy I didn't need to retrofit Trex hardwired lighting to achieve a great look. Lastly, from a service and delivery perspective, Ultra Bright Tech has been great. There was a mix up with my shipping and they proactively contacted me and refunded the difference.