Compare the2022 Audi S3VS 2021 Mercedes AMG C-Class Sedan

Both the S3 and AMG C-Class Sedan have child safety locks to prevent children from opening the rear doors. The S3 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The AMG C-Class Sedan’s child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.

The S3 has a standard Secondary Collision Brake Assist, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The AMG C-Class Sedan doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.

To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the S3. But it costs extra on the AMG C-Class Sedan.

The S3’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. A lane departure warning system costs extra on the AMG C-Class Sedan.

Both the S3 and the AMG C-Class Sedan have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, rearview cameras, available blind spot warning systems and rear cross-path warning.

The S3’s corrosion warranty is 7 years longer than the AMG C-Class Sedan’s (12 vs. 5 years).

The Audi S3’s engine uses a cast iron block for durability, while the AMG C-Class Sedan’s engines use an aluminum block. Aluminum engine blocks are much more prone to warp and crack at high temperatures than cast iron.

From surveys of all its subscribers, Consumer Reports’ January 2021 Auto Issue reports that Audi vehicles are more reliable than Mercedes vehicles. Consumer Reports ranks Audi 6 places higher in reliability than Mercedes.

On the EPA test cycle the S3 gets better mileage than the AMG C-Class Sedan:

To lower fuel costs and make buying fuel easier, the Audi S3 uses regular unleaded gasoline (premium recommended for maximum performance). The AMG C-Class Sedan requires premium, which can cost 20 to 55 cents more per gallon.

The S3’s standard tires provide better handling because they have a lower 40 series profile (height to width ratio) that provides a stiffer sidewall than the AMG C 43 Sedan’s standard 45 series front tires.

For better maneuverability, the S3’s turning circle is 2.3 feet tighter than the AMG C 63 Sedan’s (36.4 feet vs. 38.7 feet). The S3’s turning circle is 3.3 feet tighter than the AMG C 43 Sedan’s (36.4 feet vs. 39.7 feet).

The Audi S3 may be more efficient, handle and accelerate better because it weighs about 300 to 350 pounds less than the Mercedes AMG C-Class Sedan.

The S3 is 7.7 inches shorter than the AMG C 63 Sedan, making the S3 easier to handle, maneuver and park in tight spaces.

The design of the Audi S3 amounts to more than styling. The S3 has an aerodynamic coefficient of drag of .29 Cd. That is lower than the AMG C-Class Sedan (.31 to .32) and many sports cars. A more efficient exterior helps keep the interior quieter and helps the S3 get better fuel mileage.

The S3 has a 3500 lbs. towing capacity. The AMG C-Class Sedan has no towing capacity.

In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The S3 Prestige has standard headlight washers to keep headlight output high. The AMG C-Class Sedan doesn’t offer headlight washers.