I used to have a Road Toad incandescent bike light that was powered with AA batteries. Thank goodness LED lighting has fixed a lot of the issues involved with bicycle white light technology.
My biggest complaint with this older model Road Toad is that it at batteries. I got about two hours use from it before new batteries were required. As someone who usually rides at night, this is problematic.
I also found that the light did not effectively light up the road in moderately-lit night conditions (it was fine in pitch dark conditions). Sure it made me visible to motorists, but it didn't have as much range or brightness to what I wanted. It also didn't blink. Of course, this is an older model so I am not sure if that technology really was put into effect before LED lighting revolutionized bicycle headlights.
Overall, I believe this is just a story of technology passing this light by. As it appallingly ate up batteries, I would not recommend this light unless you need a cheap used one. Even then, opt for LED lighting instead.