I've been using a Princeton Tec PUSH headlight for a few weeks. The thing puts out 100 lumens off of three AAA batteries. It's brighter than any headlight I've tried–and I've tried many. And by "many" I mean "a handful of cheap ones."
It's got to be twice as bright as any of the other headlight I've used. The graphic on the box says it illuminates up to 65 meters (213 feet). I believe it.
(The graphic on the box, when flattened for my scanner, also reminded me of the scariest stop sign I've ever seen.)
The blink mode on other lights I’ve used is mostly so that vehicles will see you–not so that you can see the road. The blink mode on the PUSH has a pattern that alternates between low and high–rather than between off and high.
This means I didn't have to switch to a steady beam where my route temporarily is not lit by streetlights. People prone to photosensitive seizures probably shouldn't look directly into this light when it's in blink mode. But cyclist who want to have a disco party can definitely use it as a strobe light.
I've not reached the end of the battery life yet. Since I always use it in blink mode, that may take awhile.
I like that the light swivels on its mount about 10 degrees. This allowed me to mount it to my curved handlebars, and still have the light point straight ahead.
It has a really long mounting bolt, which meant I could mount it to my skinny handlebars without using those rubber spacer rings that come with any other light I've used.
Princeton Tec promotes the "independent light pipes that emit though side windows ensuring over 260 º of visibility." I'm not going to say that they're useless, but they were the least significant part of my lighting setup.
To save a little battery life it's possible to use the light without the light pipes. But I'm not that cheap, so I used them. What the hell. But I wouldn't spend more than, say, $2 more for this light over comparable light without light pipes.
The light retails for about $49. But I was serious about the disco thing.
Bonus: The PUSH’s Box and The Scariest Stop Sign I've Ever Seen