IT IS the fastest-selling car ever sold in Korea and a sell-out success in the United States, and now Hyundai’s striking new Sonata has arrived in Australia, where it will be known as the i45.

Available here now in three specifications, each powered by a new direct-injection 2.4-litre four-cylinder petrol engine that delivers more performance than all of its rivals in the mainstream mid-size sedan segment, the sedan-only i45 lands with a higher than expected starting price of $29,490 for the entry-level Active six-speed manual.

That’s significantly more than the outgoing Sonata’s $27,990 opening price – which is shared with Australia’s newest medium sedan, Suzuki’s all-new Kizashi – as well as its most direct rival in the recently facelifted Mazda6 range, which opens at $27,310.

As an automatic, the i45 Active costs $30,990 – more than base auto versions of the Mazda6, Ford Mondeo, Kizashi, Holden Epica and Toyota’s top-selling Camry, but less than the Volkswagen Jetta, Honda’s Accord Euro and Subaru’s Liberty.

Unsurprisingly, however, the i45 arrives stuffed full of standard equipment, including an automatic with more ratios than most of its rivals and a full suite of safety gear, including twin front, front-side and side curtain airbags, active front head restraints, electronic stability/traction control and ABS brakes with brake assist and electronic brake-force distribution.

All i45s also come standard with 16-inch alloys wheels (absent on the base Mazda6 and Mondeo), an alarm (standard only on the base Accord Euro and Camry), a hill-holder function (also offered only on the Jetta), a trip computer (standard only on the entry Mondeo, Jetta, Kizashi and Liberty), automatic headlights (fitted only to the base Camry, Mondeo and Jetta), front foglights (standard only on Liberty), steering wheel audio controls (missing from mazda6), a six-speaker AM/FM/CD/WMA/MP3 player with USB/iPod connectivity (standard only on Kizashi) and a leather-clad steering wheel (standard only on the base Mondeo, Liberty and Jetta).

The base Active variant follows the rest of the range on sale in July and was a last-minute Australian addition as a result of freer supplies from Hyundai’s Busan plant in Korea, which has the annual capacity to produce a staggering 1.6 million vehicles.

It will be luxuriously specified with cloth/leather seat trim, wing mirror-mounted indicators, LED tail-lights, dual chromed exhaust outlets and piano black interior highlights.

As with some of its rivals, however, cruise control is standard only on automatic models, while the cheaper Kizashi and pricier Liberty score larger 17-inch alloys at base level, all Kizashis also come with dual-zone climate-control and keyless starting, and satellite-navigation is not available on the i45. Metallic/mica paint adds $450 but is free with the Mazda6.

The mid-range auto-only i45 Elite costs $34,490 (the same as the superseded Sonata Elite), undercutting the Mondeo Zetec, Accord Euro Luxury, Liberty Sports, Jetta 147TSI and, narrowly, the flagship Kizashi XLS – but not the Mazda6 Classic, Epica CDXi or Camry Ateva and Sportivo.

In addition to the i45 Active’s standard equipment, the Elite adds full leather upholstery, 17-inch alloys, keyless entry and starting, rear parking sensors, automatic climate-control, rain-sensing wipers and steering wheel paddle shifters.

Priced at $37,990, undercutting its three key Japanese rivals, the Premium variant tops the i45 range and gains a panoramic glass sunroof, 18-inch alloy wheels (again with a full-size spare), sports suspension with Amplitude Selective Dampers, an electrochromatic rear-view mirror, premium sound system with six-CD in-dash stacker and integrated display screen with outside temperature display and a digital clock, and powered front seats with driver’s memory (eschewing the manual passenger seat height adjuster of downstream models).

The i45’s new long-stroke DOHC 16-valve Gasoline Direct Injection (GDI) four delivers a class-leading 148kW of power at 6300rpm and 250Nm of torque at 4200rpm, and returns average fuel consumption of 7.9 litres per 100km (8.0L/100km as a manual), joining the Kizashi in undercutting all of its direct petrol rivals except the Jetta 118TSI.

The sedan-only i45 is not available as a hatch or wagon and, unlike the Liberty and (potentially) the Kizashi, drives only its front wheels. While the Madza6, Mondeo and Jetta are also available with diesel power, the i45 should eventually match the Camry (and potentially the Kizashi) by offering a petrol-electric hybrid version. Hyundai Motor Company Australia has also received Australian design certification for a 2.0-litre version of the i45, which may also be eventually added to the range.

The second of three key new Hyundai model to arrives Down Under this year, ahead of the all-new i20 light-sized hatchback, the i45 follows the ix35 compact SUV – released here in February – in wearing the Korean car giant’s new ‘fluidic sculpture’ design theme, which in this case was created at Hyundai’s Californian design studio.

It measures 4820mm long, 1835mm wide and 1470mm high, making it shorter than all bar the Camry and Kizashi, but wider than all but the Accord Euro and Mondeo. Its 2795mm wheelbase is 65mm longer than the (old) Sonata’s, yet the i45 is only 20mm longer overall. With a base kerb weight of 1528kg in automatic guise, the i45 is slightly heavier than all of its rivals, but offers the best power-to-weight ratio of 97kW per tonne.

The i45’s boot capacity is 523 litres, bettering the Kizashi, Liberty, Accord Euro and Mazda6 sedans, but falling narrowly short of the Jetta, Mondeo and class-leading Camry (535 litres). Although its flexibility is boosted by a 60/40-split folding rear seat, the i45’s total boot capacity is limited in practice by out-dated gooseneck hinges.

Unlike many of its rivals, the i45 comes with a traditional hydraulic (rather than electric) power-assisted rack-and-pinion steering system, which delivers a tight 10.92-metre turning circle and a tight overall ratio of 2.94 turns lock-to-lock, aided by a height and reach-adjustable steering wheel.

Like all Hyundais, the i45 comes with a generous five-year/unlimited-mileage warranty and is available with a full range of optional accessories, including a Bluetooth phone kit, tailored carpet floor mats, roof racks, window visors, dash mat, headlight protectors, 16/17/18-inch alloys and a towing kit.

Exterior paint colours for the i45, which has a reasonably slippery drag co-efficient of 0.28Cd, include Noble white, Sleek silver, Espresso brown, Remington red, Passion blue, Dark Grey and Black Diamond.

The world’s fifth-largest and fastest-growing car-maker expects to sell 500 examples of the i45 each month this year in Australia, representing a 2010 total of 4000 sales and a full-year total of 6000 vehicles, with fleet sales to intially account for 30 per cent of sales, increasing to 50 per cent over the model's life cycle.

That’s well short of the sales achieved by the Mazda6 – the top-selling privately-purchased mid-size – let alone the Camry, but well up on the almost non-existent Sonata.