I've seen it, kind of useless tho since you'll spend most time in the bottom 1/3rd. My car is an American import so i got up to 180kmh, and the digital keeps going.
I have a Canadian V and it's pretty useful when you get arrested for speeding... you just switch it to Miles/H instead of KM/hours and you tell the officer "ooops sorry I just came back from the States and forgot to switch it back to KM/H"