Get an Edelux II with the new coax connector (if you have a SON dynamo hub). Schmidt also offer a small splitter box that provides a socket for another coax plug to connect a USB charger (when the light is off, otherwise the power from the hub is not enough).

AFAIK the Edelux internals/electronics come from B&M lights. But the LED cooling is better in the Edelux, therefore the better light output.