Here's a review my new dynamo light system now that I've had a chance to use it for nearly two months. The light is a B&M Luxos powered by an Shutter Precision PV-8 hub in the front wheel.

THE GOOD: It's easy to see how cyclists get hooked on dynamo lights from a convenience standpoint after using it a few weeks. I don't have to worry about charging the batteries for my main lights, and they start right up as soon as my bike starts moving. I also don't have to worry about the batteries going dead during a ride. My bike seems to ride just as fast with the dynamo system and I don't sense any additional drag, except at high speeds ironically. However, I also changed the wheels and tires on my bike when I installed the dynamo lights, so it's hard to make a direct comparison because the tires I had been using previously were slugs. My bike is probably a little lighter than it was previously, even though the new wheelset weighs more than the old one, because I removed the front rack that had been on my bike -- mainly as a place to mount my LED rechargeable light. I really like the B&M taillight, which is visible from wide angles and larger than most battery powered taillights.

THE BAD: From a cost standpoint, I remain convinced that dynamo lights don't make sense for most cyclists. My dynamo system cost more than $500 including the new front wheel with SP hub, the headlight and taillight. In contrast, you can easily buy a high quality rechargeable LED light as brighter or brighter than my B&M Luxos -- which is one of the brightest dynamo lights available -- for about one-fourth or less than the cost of a dynamo wheel and headlight. The costs for a dynamo system climb even higher if you need lights for multiple bikes, because you would need to buy at least new head and taillights for each bike. Regarding brightness, the dynamo light simply cannot compete with rechargeable LED lights. My rechargeable LED headlight (Light & Motion Urban 800) is brighter on medium than my B&M Luxos on high. Although though the dynamo light's shaped beam uses its light output more efficiently, that is offset by the poorer quality of its beam. The beam from my Luxos is very uneven, with bright areas and darker areas, making the beam appear striped. I prefer the evenly bright beam of my Urban 800 (and other rechargeable lights I have used in the past) much better than "striped" beam of my Luxos light. This is the major drawback of the dynamo light from my standpoint, and perhaps it is peculiar to the Luxos or other B&M models. Finally, a dynamo system is not very practical if you commute on several bikes because it is a hassle and much more expensive to swap the light among bikes. In contrast, I can easily swap my rechargeable LED light among bikes in about 10 seconds. I commute on all 5 of my bikes at times, but have mainly been using my touring bike since I installed the dynamo system on it. As a result, I'm getting tired of riding that bike all the time and grab one of my other bikes using the LED rechargeable light on days when there is little or no threat of rain.

FINAL POINT: One of the reasons why I got the dynamo light system is for bike touring, which I've been doing a lot more of during the past few years. I purchased the B&M Luxos light because it has a port for charging iPhones or other devices while riding. Although I haven't used the charging function yet, I assume that it will work as designed and will be a nice feature for touring. As a result, I'll be able to use my iPhone for navigation without running down the battery. I also will always have lights at my disposal if needed, without having to carry a rechargeable light and batteries. That is one of my main reasons for buying the dynamo system, although I have used it almost entirely for commuting so far. The advantages for touring would also apply for cyclists who do randonneuring and other long-distance rides.