Hi Gang!
On my commuter bike I have fitted a Union bottom bracket generator system. I have a headlight mounted to a discrete tubular bracket that mounts to the front brake anchor point on the fork. The lamp holds a 3W quartz bulb, which is the key to bright generator lighting. This lamp is night-and-day (sorry) brighter than the conventional bulb in the generator lamp on my Peugeot rando bike.
I gave the lamp a good test last night, encouraged by the discussion on this list. I rode 40km into the city (Toronto) from my suburban home to attend the AGM of our local Randonneur club. There are two stretches of bike path that I used that follow a river valley. With no ambient light from surrounding streets, I was able to judge the performance of the light in complete darkness (well, there was a moon). It wouldn't match the 20W bulb in my mountain bike lighting set up, but the mountain bike set up only lasts an hour before needing a 4 hour re-charge. This lamp is certainly adequate for commuting, and the cyclo-sportif pace of Randonneur riding. A useful supplement would be a helmet mounted lamp (if you could stand the modern appearance that detracts from an otherwise classic image) to help with reading maps, route sheets, and street signs.
I had a Shimano Nexus hub generator (the first generation - not the lighter one they offer now) on my previous commuter bike. The light was equivalent to what the Union is producing - maybe even a bit better at very low speeds. Hitting a pot hole made me aware of the considerable weight of the hub, as the bike nolonger responded to a gentle upward tug on the bars to soften the blow. There was also always a small perceptable amount of drag in the hub even when the light was not on. The Schmidt is apparently considerably better than the original Nexus hub generator. How the updated Shimano unit compares, I cannot comment.
Dale, for the classic content in this posting, the bb generator is controlled by a single sided Campagnolo Gran Sport shift lever on the seat tube.
Cheers!
Larry