Both the RLX and the G90 have standard driver and passenger frontal airbags, front side-impact airbags, driver 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, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning and available around view monitors.

The engines in the RLX have a single overhead cam for simplicity. The engines in the G90 have dual overhead cams, which add to the number of moving parts and the complexity of the cylinder heads.

The RLX Sport Hybrid's standard 3.5 SOHC V6 hybrid produces 12 more horsepower (377 vs. 365) than the G90 3.3T's standard 3.3 turbo V6.

On the EPA test cycle the RLX Sport Hybrid SMG gets better fuel mileage than the G90 3.3T AWD (28 city/29 hwy vs. 17 city/24 hwy).

On the EPA test cycle the RLX FWD V6 gets better fuel mileage than the G90 3.3T RWD (20 city/29 hwy vs. 17 city/24 hwy).

An engine control system that can shut down half of the engine's cylinders helps improve the RLX's fuel efficiency. The G90 doesn't offer a system that can shut down part of the engine.

Regenerative brakes improve the RLX Sport Hybrid's fuel efficiency by converting inertia back into energy instead of wasting it. The G90 doesn't offer a regenerative braking system.

In heavy traffic or at stoplights the RLX Sport Hybrid'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 G90 doesn't offer an automatic engine start/stop system.

The RLX has a standard cap-less fueling system. The fuel filler is automatically opened when the fuel nozzle is inserted and automatically closed when it's removed. This eliminates the need to unscrew and replace the cap and it reduces fuel evaporation, which causes pollution. The G90 doesn't offer a cap-less fueling system.

A ten-speed automatic is standard on the Acura RLX V6, for better acceleration and lower engine speed on the highway. Only an eight-speed automatic is available for the G90.

The RLX offers a standard sequential manual gearbox (SMG). With no clutch pedal to worry about and a fully automatic mode, an SMG is much more efficient than a conventional automatic but just as easy to drive. The G90 doesn't offer an SMG or a conventional manual transmission.

The RLX stops much shorter than the G90:

The RLX's tires provide better handling because they have a lower 40 series profile (height to width ratio) that provides a stiffer sidewall than the G90's standard 45 series front tires.

The RLX handles at .84 G's, while the G90 5.0 pulls only .83 G's of cornering force in a Car and Driver skidpad test.

The Acura RLX may be more efficient, handle and accelerate better because it weighs about 550 to 650 pounds less than the Genesis G90.

The RLX is 6.8 inches shorter than the G90, making the RLX easier to handle, maneuver and park in tight spaces.

The RLX uses computer-generated active noise cancellation to help remove annoying noise and vibration from the passenger compartment, especially at low frequencies. The G90 doesn't offer active noise cancellation.

The RLX has .5 inches more front shoulder room and 1 inch more rear legroom than the G90.

If the windows are left open on the RLX the driver can close them all at the outside door handle. On a hot day the driver can lower the windows at the outside door handle or from a distance using the keyless remote. The driver of the G90 can only operate the windows from inside the vehicle, with the ignition on.

Insurance will cost less for the RLX owner. The Complete Car Cost Guide estimates that insurance for the RLX will cost $690 to $5365 less than the G90 over a five-year period.

IntelliChoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the Acura RLX will be $17459 to $19137 less than for the Genesis G90.