I've always replaced the rubber band solution supplied with my Magicshine/Smudge light with one of these Electron handbar mounts (or similar):

You removed the top fitting from the mount and can unscrew the light bracket from the head unit. By adding a couple of spacers you can now screw the electron mount onto the bottom of the light headunit, and bobs your aunties live in lover, you have a much more stable mounting.
It seems everyone has been doing this, and all the spare electron mounts that will work, have sold out... so what anyone using as an alternative?

