I retro-fitted a set of H7 HID zenons last month. Absolutely delighted with the performance of them, but every now and then, when I switched them on, I'd get a bulb warning come up, tell me the right dipped beam was out. If I switched it off, and back on again, it sorted itself out. The supplier told me he could supply a pair of resistors that would fix it. I decided to leave it for the time being, as it only happened occasionally. But the last week or so, it's happened nearly every time I've switched the lights on; then, on Saturday, I got a brake lightbulb warning followed by an ABS failure warning. This stayed on until I switched the engine off, and when I restarted the car, it had gone away again. Then today, I read a thread on one of the A3 forums, where someone fitted a set of HIDs, and now his wipers have packed up. According to one of the follow-up posters, the HIDs are to blame, the wiper motor will need replacing, and even fitting resistors won't necessarily stop it happening again. So now I'm wondering whether it's even worth shelling out on a set of resistors, or whether to just cut my losses, swap the HIDs out and go back to halogens. That ABS warning light really shook me, I can tell you. If the lights can knock out my brakes, I really don't want them in there.