The PB 2 watt puts out almost as much light as the B&M led on my wife's bike which runs off a dyno, the shortcoming with any battery light is run time and with nimh rechargeables the run time is decent and I find it to be an adequate light to see by.

Higher output battery lights will often suffer from runtime issues.

My daily driver has a dynohub and BM headlight and I use the 2w as a supplemental light there but it can serve as a primary light on other bikes or be run paired with other hotter lights.