So what?
It works well, re-charges quickly, is really bright, small and lightweight. I have never had it die on me. I don't ride centuries at night though.
I have tried out all kinds of lights. From flashlight mounts to all varieties of PB and other blinkies.
Knogs suck....not bright enough.
PB superflash is good, but not great. Mine has issues with the button working properly sometimes. Especially when wet. I HATE looking back mid ride and noticing the damn thing turned off by itself.
Cheaper blinkies get dim pretty quickly, and usually require some kind of mount to be attached to each bike you want to use it on.

So for best all around be seen lighting, I go for the fleas.
Considering...
Price.
Weight.
Reliability.
Brightness.
Ease of use, and transferring between bikes.
Unlimited lifetime warranty.

I'm not trying to shill here, I have no affiliation with the company. It's just that after spending a lot of cash on all sorts of lights, I have found these to be the best for my needs.