Not to sure about the sub 100, i think it depends where you live.
Around waterlooville we have a quite a few dual and motorways and long slip roads.
There is a short stretch of 2 1/4 miles between junctions on the a3, where i can easily achieve 160 (and thats kph ;o) and then get off the next junction.
So that includes braking etc, just gave it a try when i first got the car but rarely boot it now.
I also noticed s60r speedo is pinpoint accurate compared to the sat nav and road hawk.
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