No offense intended, but I disagree- while more light can be nice, on occasion, it isn't by any means a necessity. We've had some great rides (downhills flat out), limited in no way by inadequate lighting, running lights that were less than ten watts. Actually, we've had some great rides on the old c-cell battery lights that were available 15 years ago. At the risk of overstating this, there is no minimum wattage necessary to be safe for nighttime trail riding. You may have to slow down with a tiny light, but you can still ride. And too much light, when you can't always control the direction in which you're pointing it, can be hard on approaching riders and other trail users, spoiling their night vision and endangering them.

When commuting, lots of light is nice as a way of getting yourself noticed. But 10 watts does the job, for me, very nicely, thank you very much.

I have a L&M Solo, and have been very pleased. The battery is compact and has reasonably good life, the light is tough and well constructed, and the price is closer to right, in my estimation.