The fork mounts are simple, but if you are riding fast desert stuff the frame mounted lights are more often pointed in the correct direction. If you consider setting up for and going through a highspeed turn your handlebars are not pointed were you are looking. With the bike pitched out, the beam is pointed further into the corner.
I have slot of experience with both and much prefer the frame mounts.
The articulating light mount that BD sells is made by Foes Fab.