I'm going out on a limb here, for fear of being flamed, but:
I have neons on my Leon. They were an xmas present, and so felt like I HAD to install them so as not to upset the giver of the present...
Thats not to say i don't like them though - i love them! (if done right!)
I spent a good 2-3months planning the install, so I got it right. The tubes are so perfectly placed that unless you are virtually under the car, you cannot see the tubes directly.
I also went for red coloured neons - a) because they look good and b) so that it wouldnt draw too much attention like blue and green.
Finally - so as to not be classed a "chav" - I installed the on/off switch in the boot of my car. Meaning i could only ever have them on when parked up for shows/meets etc, and so that none of my passengers could fiddle with them. I do NOT drive on public roads with them switched on.
I still think the rule is that if the tube can be seen, its illegal. I don't know where the police would stand with these new neons - its probably possible for the user to set it up so that they do glow the correct colours.