There are two 2006 Kia Optimas available – the outgoing version and an all-new model being labeled a 2006.5. The outgoing 2006 model was the first offspring of the 1998 Kia-Hyundai merger, and as such shares its basic platform with the 1999-2005 Hyundai Sonata. Although this first Optima can't promise the legendary reliability and assured resale value of the long-standing class favorites in the midsize sedan class, it could be considered a more affordable alternative for buyers with tight budget constraints.

A better choice, though, is the 2006.5 Kia Optima. Improved in terms of features, rear seat room and refinement, the new Optima provides a considerably better driving experience. Additionally, Kia adds something that was lacking in the prior Optima – fun. With a suspension tuned by a former Mazda chassis engineer, the new Optima, especially when equipped with the available 17-inch wheels and 50-series tires, makes for an enjoyable drive on a twisty road. Other key factors that make this neatly tailored, budget-priced sedan worth serious consideration include its roomy cabin, solid build quality, generous list of standard and available features (including those of the safety variety), long warranty (10-year/100,000-mile powertrain coverage and five-year/60,000-mile bumper-to-bumper coverage) and handsome styling.

The Optima line comprises two trim levels – well-equipped LX and luxury-themed EX. Standard equipment highlights for the LX include a CD player; air-conditioning; power windows, locks and mirrors; a 60/40-split-folding rear seat; and cruise control. If you opt for the LX V6, alloy wheels are added to the mix. Step up to the EX and the following features are added: a power driver seat, automatic climate control, upgraded cloth upholstery, an auto-dimming rearview mirror, alloy wheels, foglights and an Infinity audio system with six-disc CD changer and cassette player (2006.5). On the options roster you'll find an upgraded sound system for LX models and a leather upholstery package (with a power front-passenger seat) for EX models. Available on all 2006.5 Optimas but the four-cylinder LX is a safety package that includes antilock brakes with brake assist, traction control and stability control. Also optional on 2006.5 models is an appearance package with a blacked-out grille, 17-inch wheels, foglights and aluminum interior accents. A power moonroof is optional only on the EX.

The 2006 Optima LX offers a 2.4-liter inline-4 with 138 horsepower. A 170-hp, 2.7-liter V6 is optional on the '06 LX and standard on the 2006 Optima EX. The 2006.5 models are more powerful: The standard 2.4-liter engine provides 161 hp, while the V6 is capable of 185 hp. That's still not a lot of power compared to most other V6 family sedans, whose engines pump out well over 200 hp, but the Optima's six-cylinder is at least smooth and quiet. A five-speed manual transmission is standard with the four-cylinder engine, and an automatic (a four-speed for 2006, a five-speed for 2006.5) is optional. Only an automatic gearbox (four-speed for 2006, five-speed for 2006.5) can be paired with the V6.

If you're shopping the 2006 Kia Optima, we recommend the V6, but if you're considering the 2006.5 model, the peppy inline-4 is the one to get – its performance may surprise you. Fuel economy for the 2006 versions is 23 mpg city/30 mpg highway with the four-cylinder and 20/27 with the V6, while for 2006.5 Optimas the stats are 24/34 (inline-4) and 22/30 (V6).

On 2006 Optimas, only V6 models are eligible for optional ABS. Side airbags for front occupants and three-point seatbelts for all five seating positions are standard across the board. The 2006 Kia Optima earned four stars for driver and front-passenger protection in frontal impacts and a four-star rating for front- and rear-occupant protection in side impacts. The IIHS gave the 2006 Optima a rating of "Acceptable" (the second highest of four) for its frontal-offset crash test. In IIHS side-impact testing, the Kia rated "Poor" (the lowest).

On the redesigned 2006.5 Optima, side curtain airbags are standard on all models, while stability control and ABS are available on all but the base four-cylinder LX. In NHTSA crash tests, the 2006.5 Optima earned a top five-star rating for its protection of occupants in frontal and side impacts.

Either version of the Optima will provide comfortable transportation for the day-to-day grind, though the newer Optima adds a healthy dose of sporting personality and is more adept at absorbing the nastiest bumps and potholes. Light and precise steering and a somewhat floaty ride dynamic mark the 2006 Kia Optima, while the redesigned sedan provides more road feel and a more buttoned-down attitude when tackling a twisty road.

The 2006 Optima's cabin is attractive, with comfortable seating and good build quality, though more rear-seat legroom is found in some competitors. Controls are simple to use and there are plenty of places to stow things like cell phones, change and parking cards. Improvements that came for 2006.5 include more upscale materials, more legroom for the backseat and more upscale features, such as blue/white instrument illumination and power-adjustable pedals. Trunk capacity, at 14.8 cubic feet, is roughly 1 cube greater in the 2006.5 version and as before features a low lift-over, large opening and hidden hinges to ease loading.