[andruby]

That's interesting, in Belgium I think it's "2 seconds", or at least that's what was promoted recently on the radio.

You should be able to sing "Last night a DJ saved my live", which is a bit more than 2 seconds. I liked that, because it's one you can actually test for while driving.

I find it a lot harder to estimate 50m while driving at 100km/h

[lqet]

The reflector posts are always exactly 50 meters apart, which makes this relatively easy.