Another option is mounting the driving lights above the side mirrors, just like on the Kawi cop bikes. I did it and it works great and looks great too. I believe I got the mounts from Kawasaki Authority Sales, one of the outfitters for the police bikes. Beaudry Motorsports is the other supplier of police bikes. Btw Rigid Industries Dually 2 lights are awesome!
That probably is the best place. It is robust, least likely area to get hit by a rock/etc, doesn't stick out a lot, gives better aiming control to prevent blinding people, looks pretty good, and best angle. Not a good location for *FOG* lights, but great for driving/high-beam tie-in. Maybe some day I will do that.