I have a plug n play set on my 08... daytime running lights are bit messed, so i just leave lows on, and my driver side high beam doesnt swift to halogen. Sometimes when I go from stop to go at a red light or such, My HID's will quickly turn on and off for 1 second.. quick flash... These are all problems I can fix, and the colder it is, the more the flicker will happen.. But I have researched that resistors will fix the flickers, and I have them sitting on my desk waiting for it to warm up outside.
All in all, HID's are alot better lighting then halogens, dont even need high beams.
Brandon...Check out my build thread here