For enhanced safety, the front and rear seat shoulder belts of the Mercedes C-Class Sedan have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision. The Kia K900 doesn’t offer pretensioners for the rear seat belts.
The C-Class Sedan offers all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The K900 doesn’t offer all-wheel drive.
The C-Class Sedan’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The K900 doesn’t offer a driver alert monitor.
Both the C-Class Sedan and the K900 have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, height-adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available lane departure warning systems, blind spot warning systems and around view monitors.
For its top level performance in all IIHS frontal, side, rear impact and roof-crush tests, and with its optional front crash prevention system, the Insurance Institute for Highway Safety grants the C-Class Sedan the rating of “Top Pick” for 2017, a rating granted to only 107 vehicles tested by the IIHS. The K900 has not been tested, yet.
The C-Class Sedan’s 5 year corrosion warranty has no mileage limitations, but the corrosion warranty on the K900 runs out after 100,000 miles.
J.D. Power and Associates’ 2016 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Mercedes vehicles are more reliable than Kia vehicles. J.D. Power ranks Mercedes 12th in reliability, above the industry average. With 18 more problems per 100 vehicles, Kia is ranked 17th.
The AMG C43 Sedan’s standard 3.0 turbo V6 produces 8 lbs.-ft. more torque (384 vs. 376) than the K900’s optional 5.0 DOHC V8.
On the EPA test cycle the C300 Sedan RWD gets better fuel mileage than the K900 V6 (24 city/34 hwy vs. 17 city/25 hwy).
In heavy traffic or at stoplights the C-Class Sedan’s engine automatically turns off when the vehicle is stopped, saving fuel and reducing pollution. The engine is automatically restarted when the driver gets ready to move again. (Start/Stop isn’t accounted in present EPA fuel mileage tests.) The K900 doesn’t offer an automatic engine start/stop system.
The C-Class Sedan’s standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs on the K900 are solid, not vented.
The C-Class Sedan stops much shorter than the K900:
60 to 0 MPH
The C-Class Sedan’s optional 225/40R19 front and 245/35R19 rear tires provide better handling because they have a lower 40 series front and 35 series rear profile (height to width ratio) that provides a stiffer sidewall than the K900 V8 Luxury’s 45 series front and 40 series rear tires.
Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires available on the C-Class Sedan can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The K900 doesn’t offer run-flat tires.
The C-Class Sedan offers an available driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The K900’s suspension doesn’t offer adjustable shock absorbers.
The C-Class Sedan has a standard automatic front and rear load leveling suspension to keep ride height level with a heavy load or when towing. The C-Class Sedan’s height leveling suspension allows the driver to raise ride height for better off-road clearance and then lower it again for easier entering and exiting and better on-road handling. The K900 doesn’t offer a load leveling suspension.
The C-Class Sedan’s drift compensation steering can automatically compensate for road conditions which would cause the vehicle to drift from side to side, helping the driver to keep the vehicle straight more easily. The K900 doesn’t offer drift compensation steering.
The C300 Sedan 4MATIC handles at .87 G’s, while the K900 V8 Luxury pulls only .80 G’s of cornering force in a Motor Trend skidpad test.
The C300 Sedan 4MATIC executes Motor Trend’s “Figure Eight” maneuver 2 seconds quicker than the K900 V8 Luxury (26.3 seconds @ .7 average G’s vs. 28.3 seconds @ .61 average G’s).
For better maneuverability, the C-Class Sedan’s turning circle is .7 feet tighter than the K900’s (36.8 feet vs. 37.5 feet).
The Mercedes C-Class Sedan may be more efficient, handle and accelerate better because it weighs about 850 to 900 pounds less than the Kia K900.
The C-Class Sedan is 1 foot, 4.1 inches shorter than the K900, making the C-Class Sedan easier to handle, maneuver and park in tight spaces.
The C-Class Sedan’s standard rear seats fold to accommodate long and bulky cargo. The K900 doesn’t offer folding rear seats, only a ski pass-through.
Unlike the driver-only memory system in the K900, the C-Class Sedan offers an optional passenger memory, so that when drivers switch, the memory setting adjusts the driver’s seat, steering wheel position and outside mirror angle and the front passenger seat also adjusts to the new passenger’s preset preferences.
If the windows are left down on the C-Class Sedan the driver can raise them all using the key in the outside lock cylinder or the keyless remote; on a hot day the driver can lower the windows. The driver of the K900 can only operate the windows from inside the vehicle, with the ignition on.
While driving with high beams on, sensitive light sensors available for the C-Class Sedan detect other vehicles which could be blinded and automatically switch to low beams. The K900 doesn’t offer automatic dimming high beams.
The C-Class Sedan’s optional Active Parking Assist can parallel park or back into a parking spot by itself, with the driver only controlling speed with the brake pedal. The K900 doesn’t offer an automated parking system.
Motor Trend performed a comparison test in its January 2015 issue and they ranked the Mercedes C300 Sedan 4MATIC higher than the Kia K900 V8 Luxury.
The C-Class Sedan was chosen as one of Automobile Magazine’s “All Stars” in 2015. The K900 has never been an “All Star.”
The Mercedes C-Class outsold the Kia K900 by almost 63 to one during the 2016 model year.