I always thought the wrist lights would not work well. Being on the back of the hand, they cannot illuminate whatever you're doing with your hands because your hand would block them, unless you turn your OTHER hand downward and use that light. In which case, the light ties up one hand just like a flashlight would. They are not pointed right for a weapon light either - you'd have to use some kind of one handed duellist's stance.
A head light would better.
When I first saw them on Star Trek (I think ST/TNG used them first), I thought how primitive the wrist lights looked for something 3 centuries in the future. By then, I would expect a horde of nano-lights to be flying around you which just put light wherever you want, whenever you want, like a powerful, focused, adaptive halo.
Hmmm...
Anyway, too expensive to make that special effect, so wrist lights it is.