I've been tinkering between HID's and LED's for a bit now,
HID's are more trouble than they are worth and I've ended up having nothing but issues.
Apart from being a bit slow to warm up they don't have great longevity and nor are they cheap to replace.
HID's HATE being turned on and off, so with cars now having Auto headlights I absolutely cringe in the Mrs car when we drive under a bridge for a few seconds and it turns the lights on and by the time they warm up they're back off again.
As soon as 1 of the globes blew, I replaced it with LED. I bought the globes that plug directly into the Ballast as I can't be bothered re-wiring them for now.