Ill help you out here, I have had 3 MOT's with Xenon's fitted and all passed fine, I was not using projectors either on my B5 there are plenty of pics and videos on my webby
My website I now have a B6 audi quattro with non xenon projectors, and have fitted them in there, the light cut off is almost the same as xenon projectors, there is nothing "yet" in the MOT testers handbook about having xenon/HID lights in a car, or retro fitting them, although they are trying to make it illegal in the states.
You can fit self levelers quite easy, you just replace your old motors with the new ones, basiclly self levelers are just small motors with a tilt sensor that when you travel uphill or have loads in the car componsate buy lowering/raising the beam.
I would say though, I have noticed this year in the UK my lights get dirty real quick, and I had washers on my B5 quattro, this time I dont have washers and it makes the lights a bit dimmer when driving at night, So I do tend to wash my lenses alot, when I fill up etc.
hope this helps
Ronny