I added some hyper lites to my litre strom yesterday and really like the effect. They are extremely noticable when I hit the brakes. You'd have to be nearly blind not to notice them. I commute 300-500 miles per week and have had too many close calls.
I wanted to mount them as high as possible somewhere that would not interfere with my soft bags, or require any connector/wiring with the top case. They are angled slightly inward but the reflection off the rack ensures max brightness straight back. I added a connector under the rack to make removal very easy. Wiring was as per the instructions, very easy.
The image is a little misleading. The flash makes them look lit and white. They are off in the pic. They are very red and flash when the brakes are used as seen here in this quicktime video I took of them:
For mine, you tap into two brake light wires on the bike, crimp two others (included in the package), mount the flasher unit under the fender, mount the light unit on top of the license plate light and ride away whistling.... or flashing, as the case may be