They're so cheap because they're a cheaply made no name brand. Lots of people have had problems with no name HIDs and even some of the lesser name brands out there. Philips/Hella seems to be the most reliable, though you'll be shelling out around $400 for a kit. Another alternative, if you're looking for better light output, is the H7/H9 hybrid bulbs that DanielSternLighting.com is selling. They offer almost 30% more output than stock. Not like those "30-50%" more light bulbs from Philips or Sylvania, we're talking 2100 lumens vs 1500.