Right out of the box, I'm impressed. Mind you, the lightbox it's replacing is about fifteen years old, four inches thick and uses a florescent bulb, but this thing is incredibly thin and lightweight.
It's pretty intuitive. There's only one button. Tap it to turn it on/off, hold it to change brightness.
It's also USB powered which means you can run it off of your laptop or even an external battery allowing maximum portability.
It could be just a tad brighter, but I don't think that's actually going to be a problem.