I've had HID low and Hi beams since I bought my bike.. I paid a little extra for the lights from XenonRider but was impressed with their quality and their customer service.
After 4 years I had my first failure, the LARGE ballast/Igniter died, the two ultra-slims are still plugging along and have lost zero bulbs..
The ballast I lost was one of the low beams so had to tear apart the front of the bike to swap ballasts around, so the last week I had low beams and no hi..
4 years before the first failure, and what's interesting I think I had minor issues with this ballast from the beginning but it always self corrected...