Magnus Innovations lights are probably reasonably good for their price (cheap!) but you get exactly what you paid for.

I had front and back light from them. Still have the front one. Back light was not very bright, can't say much else about this light as I lost it on the first ride. Front light is just a regular Chinese flashlight with 18650 battery with typical flashlight spot lighting pattern. On its high setting light lasts about 30 seconds, one minute on a good day, then automatically reduces brightness and starts blinking that it is discharged but still continues working fine on medium brightness for at least half an hour, usually more. Unless it is cold outside - in winter charge lasts about 15-20 minutes. After a few rides button that turns the light on felt off and PCB behind it became visible. Now I need to press switch on the PCB directly to turn the light on or off. If it rains, water gets on the PCB and light turns on automatically by itself - and stays turned on until all water dries out, battery discharges or gets removed - it is not possible to turn it off by the switch while it is wet. Already survived a dozen of heavy rains. Seems to be built like a tank, you can probably use it for self defense successfully.