Long highway trips, how does the Celerio fair against the city?

Many owners use the Celerio for longer journeys, but it is often sold as an ideal city car. Essentially this question is asking how versatile and how well the car does outside its primary urban use? For example, high speed stability, comfort on long distance, fuel efficiency on highways than city conditions, and adequacy of power for overtaking maneuvers are important. Real world experiences of owners who have taken their Celerios on road trips are discussed and compared with other cars in its segment and even some from the higher segments. It also explores car's practicality for families who'd like to have it as their only vehicle for both daily commute and occasional long drive.