A month ago I was in a group ride with a bunch of seniors.  Half the riders were on ebikes-I was riding my regular Specialized Diverge carbon.  I got tired of riding at their pace and took off.  I got so far ahead of them I could no longer see the LED headlights from the ebike riders.
While cruising along, at around 27kph, on a long, straight road I could see a headlight way, way back gaining on me.  I maintained my speed and within a couple of minutes that rider I'd seen way back had caught up to me. 
The rider, who is 82 years old,  was on a Specialized Vado 5.  This is one impressive ebike.