The RLX's pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The ES Series doesn't offer pre-crash pretensioners.

The RLX has standard whiplash protection, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the whiplash protection system moves the headrests forward to prevent neck and spine injuries. The ES Series doesn't offer a whiplash protection system.

The RLX Sport Hybrid has all-wheel drive to maximize traction under poor conditions, especially in ice and snow. The ES Series doesn't offer all-wheel drive.

Both the RLX and the ES Series have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front seatbelt pretensioners, front wheel drive, 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, rearview cameras and available around view monitors.

The National Highway Traffic Safety Administration does 35 MPH front crash tests on new vehicles. In this test, results indicate that the Acura RLX is safer than the Lexus ES Series:

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

There are over 12 percent more Acura dealers than there are Lexus dealers, which makes it easier should you ever need service under the RLX's warranty.

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

The RLX's standard 3.5 SOHC V6 produces 95 more horsepower (310 vs. 215) than the ES 300h's standard 2.5 DOHC 4 cyl. hybrid. The RLX's 3.5 SOHC V6 produces 8 more horsepower (310 vs. 302) and 5 lbs.-ft. more torque (272 vs. 267) than the ES 350's standard 3.5 DOHC V6. The RLX Sport Hybrid's standard 3.5 SOHC V6 hybrid produces 75 more horsepower (377 vs. 302) and 74 lbs.-ft. more torque (341 vs. 267) than the ES 350's standard 3.5 DOHC V6.

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

The RLX Sport Hybrid's standard fuel tank has 1.9 gallons more fuel capacity than the ES Series Hybrid's standard fuel tank (15.1 vs. 13.2 gallons), for longer range between fill-ups. The RLX's standard fuel tank has 2.6 gallons more fuel capacity than the ES Series' standard fuel tank (18.5 vs. 15.9 gallons).

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 ES Series 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 ES Series.

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 ES Series doesn't offer an SMG or a conventional manual transmission.

For better stopping power the RLX's brake rotors are larger than those on the ES Series:

The RLX stops much shorter than the ES Series:

For better traction, the RLX has larger tires than the ES Series (245/40R19 vs. 215/55R17). The RLX's tires are larger than the largest tires available on the ES Series (245/40R19 vs. 235/45R18).

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 ES Series' standard 55 series tires.

For better ride, handling and brake cooling the RLX has standard 19-inch wheels. Smaller 17-inch wheels are standard on the ES Series.

The RLX has standard front and rear gas-charged shocks for better control over choppy roads. The ES Series' suspension doesn't offer gas-charged shocks.

For better handling and stability, the track (width between the wheels) on the RLX is 1.5 inches wider in the front and 1.1 inches wider in the rear than the average track on the ES Series.

The RLX handles at .84 G's, while the ES 300h pulls only .78 G's of cornering force in a Motor Trend skidpad test.

The RLX executes Motor Trend's “Figure Eight” maneuver 1.6 seconds quicker than the ES 300h (26.8 seconds @ .67 average G's vs. 28.4 seconds @ .6 average G's).

The RLX has 2.2 cubic feet more passenger volume than the ES Series (102.1 vs. 99.9).

The RLX has .1 inches more front headroom, .9 inches more front hip room, 3.7 inches more front shoulder room, .2 inches more rear hip room and 2.7 inches more rear shoulder room than the ES Series.

To allow full utilization of available cargo room, the RLX's trunk lid uses concealed beam hinges that don't intrude into the trunk. The ES Series' useful trunk space is reduced by its intrusive beam hinge.

The RLX's standard easy entry system raises the steering wheel and glides the driver's seat back, making it easier for the driver to get in and out. An easy entry system costs extra on the ES Series.

The RLX's rain-sensitive wipers adjust their speed and turn on and off automatically based on the amount of rainfall on the windshield. This allows the driver to concentrate on driving without constantly adjusting the wipers. The ES Series' standard manually variable intermittent wipers have to be constantly adjusted.

Consumer Reports rated the RLX's headlight performance “Good,” a higher rating than the ES Series' headlights, which were rated “Fair.”

The RLX has standard heated front seats. Heated front seats cost extra on the ES Series. The RLX Sport Hybrid also has standard heated rear seats to keep those passengers extremely comfortable in the winter. Heated rear seats aren't available in the ES Series.