See https://www.youtube.com/watch?v=_-d5pZ6lmsM some seasoned skateboarders trying out an E-GO for the first time.
As far as speed goes, an E-GO Cruiser travelling at 20 km/hr or 13mph can
-- Cruise along at 5.5 meters / 18 feet every second
-- Can cross a doubles tennis court in under 2 seconds
-- Can do a length of an Olympic size Swimming Pool in 9 seconds before the Olympians have even got half way
-- Can do an American football field end zone to end zone in under 20 seconds
-- Travels at about twice the speed of an average marathon runner over the same distance
-- After your friend gives up after 500 metres running along side you, you carry on for another 20,000m +