[Mini_me]

If I remeber correctly xenons light have to have the high pressure washers by law... though I'm in Germany so not sure if that also applies to the UK.
On my early MK I (2002) R53 I have dipped beam exenon headlights. That don't flicker at startup (at least not that I have noticed), but they do do the levelling thing within the first few seconds - they self adjust from pointing down to raising up more to normal position.