Since Toyota launched the Prius—the world’s first mass-produced hybrid vehicle—in Japan in 1997, it has become far and away the best-selling hybrid car in the world. Toyota began selling it in North America, Europe and elsewhere in 2000, and has sold nearly a million worldwide since 2001.

The Guardian recently interviewed some Prius owners to see what all the fuss is about. Here are some of the things British owners had to say about their Prius, which helps reveal its wide-ranging appeal:

“I drive differently now - I avoid over-revving, and seek to get the best mpg out of the car. I've been on some Prius websites to get tips on mpg. The average since I got it is 57.5mpg, but more recently, since getting a tyre inflator and checking the tyres more often, it's been 60mpg.”

“The seats are comfortable, it's surprisingly spacious, and things like satnav and the camera for reversing are an added bonus.” 

“I think it is probably true that the car imposes calm. I like driving quite fast - I'm not going to say how fast, but my speed is probably now a bit lower than it was.”

“The Prius is very nice to drive, for someone who doesn't like driving. It's completely automatic - it's got fewer gears than our lawnmower. You glide along. I can't imagine having road rage with this car.”

“You want to drive in a greener way. You look at your miles per gallon - not for financial reasons, but purely to see how you're doing. Mine is around 50mpg.”

“I do like the car. It's got lots of gadgets and information…If I were to go shopping in town, I might take the car because of not having to pay the congestion charge, but until now I've always gone by train.”

“There is also more head space in the Prius. I'm 6ft 5in and it's a very good size for me. My father, who died recently, used to wear a hat in the 50s and 60s, and he would only buy a car that he could fit in with his hat on. His first car was a VW Beetle. My father could have fitted in a Prius.”

In January of this year, hybrid car makers sold 22,392 units in the U.S., an increase of 27 percent over January, 2007. And as usual, Toyota sold the most hybrids, with 18,652 units sold, or 83.3% of the market. And while the Prius is still the most popular hybrid, it’s not the most CO2-efficient car you can buy. However, if you want to beat the Prius' CO2 rating, you might find yourself a bit cramped inside. Some of the current contenders for best CO2 rating include the VW Polo Bluemotion, the Mini Cooper Diesel,  and the Seat Ibiza Ecomotive.