Although I haven't yet visited their website, the short video clip is very impressive. I wasn't aware of this product but if it's cheap enough and offers decent longevity through robust build and protection, it should be a winner.
Gulp!..........Well, I rarely ride in the dark and my bikes all have pretty decent lights fitted as standard and no battery replacement required so I can save myself a few bob for something else.
Nice idea though and the product might appeal to some heavy-duty commuters.