Tempting at $167.99

https://www.nashbar.com/bikes/Product...6_10000_201437

looks very tempting....but I think you can get as much if not more light from some LED lights for about the same $. LED's last a lot longer and can be turned on/off without messing with bulb life the way an HID bulb does.
Here's and LED I'd consider:CygoLite Rover II Xtra LED Headlight
https://www.performancebike.com/bikes..._400014_400158

I know. I like the runtime. However, I already have a Lume light and one P7 beats it hands down. The Lume is just too white.