Under the skin, its related to sister firm Hyundais i20, but Kia has developed the chassis further; it even carried out testing in the UK make sure the Rio copes well with our road surfaces.
Buyers can choose from 1.25- and 1.4-litre petrol engines and a 1.4-litre diesel, while a new 1.1-litre diesel that emits just 85g/km of CO2 and averages a whopping 88.3mpg joins the line-up early next year. A three-door version of the Rio will go on sale around the same time.
Whats it like to drive? We drove the 1.4-litre petrol model, which is more efficient and more powerful than the equivalent versions of the Fiesta and Polo. The engine is at its best when you rev it hard, but its also flexible enough to let you trundle along in traffic in a high gear.
Just dont expect the Rio to be as much fun to drive as a Fiesta; which feels sharper and more agile. The Fiestas steering is more precise, too: the Rios feels rather vague and unresponsive around the straight-ahead position.
The Rio is closer in character to the Polo, offering impressive high-speed stability and handling thats predictable and safe. The ride feels a bit jittery on patched-up urban roads without ever becoming harsh or uncomfortable. It improves with speed, too.
Perhaps the Rios greatest strength is its refinement. Few superminis are as good at shutting out wind- and road noise, and the engine is smooth.
Whats it like inside? The cabin is smartly styled, and it feels classier than a Fiestas. However, quality still falls a little short of the class-leading Polo's because the Rios upper dashboard plastics arent as soft and some of the trim on the doors is rather shiny.
The layout of the controls is hard to fault, and its easy to find a comfortable driving position thanks to the wide range of seat and steering wheel adjustment. Theres generous passenger space for four, and a large, well-shaped boot, although the split-folding rear seats dont fold down completely flat.
Should I buy one? Prices start at 10,595, for a 1.25 petrol in entry-level 1 spec. The 1.4 2 that we drove costs 13,095. Thats just 300 less than the equivalent Fiesta and 130 less than the equivalent Polo, although the Rio is slightly better equipped and it comes with a seven-year warranty, rather than the three-year version supplied by Ford and Volkswagen.
Kia is also offering a 259 package that covers all routine maintenance for the first three years, and anyone that orders a Rio before the end of September will be eligible for an early-buyer reward worth 750.
Overall, the new Rio is a huge step forward from its predecessor, and a genuine alternative to more established rivals. You can find out if its good enough to beat Fords Fiesta, Volkswagens Polo and Toyotas all-new Yaris in the November issue of What Car?, which goes on sale on September 22.
What Car? says