Ive been running a Shimano 71 (ultegra-XT) dynohub for almost a year and it has performed flawlessly. My only concern is in 2 or 3 years when it comes time to service the bearings, this is a tricky procedure requireing some care You dont want to sever the live wire by mistake.
It powers an IQ Fly which puts out plenty of illumination, well shaped for any road riding and good for low speed tracks.


Previously I powered halogen bulb dynamo headlamps using either a 6v battery or a sidewall bottle dynamo. The battery is useful on slower sections and in the mud/rain but needs management.
The bottle dynamo on my touring bike was for occasional use but I ended up riding one winter of daily commutes. The secret of a good sidwall setup is a secure and ridid mount so the spring can press against the tyre rather than rotate the mount.