I run this light, the near-field version on a Shimano 3N80 dynohub--just got it. It's more than bright enough in the area it illuminates; it's like a mini car headlight, just narrow. The specs don't tell much of the story, since while the light is nothing super in terms of raw output, it makes very effective use of the light it has with its shaped and directed beam.

There's none of that middle bright spot with a mediocre spill of light that is barely adequate on regular flashlights. I used to use a Fenix LD20 (a regular flashlight), which... just didn't work as anything better than serviceable. In terms of raw output it's similar to the IQ CYO, but at max, the spot in the center is too bright, the sidespill too dim. The IQ CYO on the other hand has a very evenly lit inverted trapezoid of light from near to far. Not to mention it can run at it's max intensity as long as I'm going about 4-5Mph (a brisk walk holding the bike). The battery light at max only goes for a couple hours--less when it gets cold.

The only thing I don't like about my IQ CYO RT is that I wish the beam was a bit wider, even if it was a bit dimmer. It seems more than bright enough in the area it illuminates already, and I feel they could spread it out a bit more. Sometimes it feels like you're ridding on a claustrophobic path, especially if you speed up.

Been eying that Phillips LED SafeRide dynamo light as a future upgrade...
http://www.bike24.net/p219881.html