Head- and tail lights definitely help make bicycles visible from the front and back, but what about from the sides? The handlebar-plug-replacing SideLights are designed to address that shortcoming, plus they serve as headlights, tail lights and turn indicators.
The thing is pretty nice, the price, not so much. Also the lumen is pretty low, at 300lumen highest setting per lamp you still need a high lumen for riding in darkness if you plan to see anything ahead.
I’m guessing they’re supposed to be in addition to a headlight…
I think they’re neat, make 'em cheap enough, brighter, rotatable so bar geometry is irrelevant, and move the controls somewhere ergonomic, and you’re heading towards a no-brainer. Although some 3d printer person might eat your lunch…