I thought the very same thing, but bought one because it was very cheap and has a large battery.
The UI is actually quite good. When you activate the side LEDs it goes to constant white light, and you can turn it off directly from there, skipping all the annoying blinky modes.
My light has a bit of a flaw, though: Sometimes it will register additional clicks, that is, inputting two clicks may have the effect of three and three may have the effect of four. One time, a single click turned on the light (which is supposed to be double click). I guess the debouncing isn’t implemented well enough (this type of button usually generates multiple signals when you press it, filtering the unwanted signals out is called debouncing).
Does anybody else observe this on their light?
Also, a cautionary note: I did some battery temperature measurements. In UV mode, the light produces excessive heat, enough to damage the battery if left running continuously (see details here ).