Comparative Automotive Research has identified no less than 30 advantages that the BMW M3 Convertible has over the Lexus IS C.

Engine

Power-to-weight ratio illustrates the relationship between curb weight and horsepower (Curb Weight / Horsepower). As a rule, the lower the ratio, the faster the vehicle. The M3 Convertible, has a lower power-to-weight ratio than the IS C, as detailed below by trim level and engine:

			Power To Weight Ratio
	M3 Convertible		10
	IS C 250 2.5L V6		18.8
	IS C 250 MT 2.5L V6		18.8
	IS C 350 3.5L V6		12.7

The M3 Convertible offers a Standard oil gauge enabling the driver to monitor the engine's oil pressure. An oil gauge is Not Available in the IS C.

Reliability

Stop and go traffic, towing and driving in hot weather all cause additional stress on you engine, increasing the engine oil temperature, reducing its ability to lubricate, cool and prevent premature component fatigue. The M3 Convertible combats these problems by providing a Standard engine oil cooler. Such a cooler is Not Available in the IS C.

To prevent the engine block from cooling down too much during extremely cold weather, which can make the engine difficult to start, an engine block heater is Standard in the M3 Convertible. A engine block heater is Not Available in the IS C.

Transmission

The Optional adaptive automatic transmission in the M3 Convertible is a computer-controlled system that automatically adapts response and performance according to driving styles and road conditions. For example, the system selects optimal shift points and determines the proper gear necessary to climb steep grades or drive downhill. This type of transmission is Not Available in the IS C 250 MT.

The M3 Convertible has a Optional manually interactive automatic transmission. This type of automatic transmission gives the driver complete gear control, like a manually-shifted transmission, but without the inconvenient clutch. The type of transmission is Not Available in the IS C 250 MT.

Corrosion Warranty

BMW's corrosion warranty provides better protection than Lexus's. This warranty protects against rust-through (sheetmetal perforation).

			Corrosion Warranty Months
	M3 Convertible		144
	IS C		72

Airbags

Both the M3 Convertible and the IS C feature Standard driver and passenger air bags.

Children and smaller adults may not be safe in a seat with a front passenger airbag. In fact, front airbags can be especially dangerous to rear-facing carseats. The M3 Convertible features a Standard passenger airbag cutoff switch, allowing the the front passenger airbag to be manually deactivated. A deactivation switch is Not Available in the IS C.

General Safety

According to the National Highway Traffic Safety Administration, heavier vehicles are safer in collisions and less affected by crosswinds than lighter vehicles. The M3 Convertible is heavier than the IS C, shown below by trim level and transmission type:

			Curb Weight MT
	M3 Convertible		4145 lbs.
	IS C 250 MT		3840 lbs.

The M3 Convertible is equipped with Standard RWD.

Most modern fuel injection systems utilize a high-pressure fuel pump that can empty a vehicle fuel tank if the fuel line is severed as a result of an accident. The M3 Convertible features a Standard emergency fuel shutoff device that measures specific G-force impact, disabling power to the fuel pump if there is an accident, significantly reducing the chance of a hazardous fuel spill. This emergency system is Not Available in the IS C.

A Standard locking fuel door/cap on the M3 Convertible is a safety feature that prevents unwanted access to the vehicle's fuel tank. This safety feature is Not Available on the IS C.

The M3 Convertible has Standard cornering lights, which are activated with the turn signals, to provide additional lighting in the direction the vehicle is turning. These lights are Not Available on the IS C.

High intensity discharge (HID) headlights are Standard on the M3 Convertible but Optional IS C. HID headlights offer several advantages - increased visibility due to significantly brighter light, longer lasting/more durable bulbs and much lower energy use.

For improved driving safety in inclement weather, the M3 Convertible features Standard windshield wiper activated headlights - a system that automatically activates the parking lights and headlights after the wipers have been turned on. This feature is Not Available on the IS C.

The M3 Convertible has Standard rain-sensing windshield wipers that are activated by rain or moisture on the windshield. This type of wiper is Optional on the IS C.

Interior Space

The M3 Convertible has more interior space than the IS C in the following areas:

			Shoulder Room, Front		Head Room, Rear		Shoulder Room, Rear
	M3 Convertible		55.3 in.		36.5 in.		49.3 in.
	IS C		54.2 in.		36.1 in.		44.7 in.

Cargo Space

The M3 Convertible has a Optional rear seat pass through, allowing very long items, like snow skis to be transported inside the vehicle. A rear seat pass through is Not Available in the IS C.

The M3 Convertible features a Standard second row folding seat for increased cargo space. A second row folding seat is Not Available in the IS C.

General Suspension

The M3 Convertible features a Optional adaptive variable suspension that can electronically sense and adapt to changing road surface conditions to provide optimum vehicle handling characteristics. This type of suspension is Not Available in the IS C.

Chassis

The M3 Convertible is shorter than the IS C , 181.7 in. vs. 182.5 in., so it will be easier to handle and maneuver.

The 'track' (distance between the wheels), of the M3 Convertible is greater than that of the IS C. A wider track produces better handling and a more stable ride.

			Track, Front		Track, Rear
	M3 Convertible		60.6 in.		60.6 in.
	IS C		60.4 in.		60.4 in.

The M3 Convertible's wheelbase is longer than the IS C's, 108.7 in. vs. 107.5 in., producing a smoother ride and more stable handling.

Wheels and Tires

The M3 Convertible comes standard with lower profile, 40 series tires (height to width ratio), which may provide better handling than the 45 series tires standard on the IS C.

Additional Features

The M3 Convertible has a Standard front power memory seat. This feature allows the driver to store their customized seating position then conveniently activate it when they get into the vehicle. A front power memory seat is Optional in the IS C.

The M3 Convertible has a Standard lockout/override feature for its power windows. This allows the driver to disable to power window controls, preventing small children from accidentally rolling down the rear windows. This window lockout/override feature is Not Available on the IS C.

The M3 Convertible offers a Standard power trunk lid as a convenience. A power trunk lid is Not Available on the IS C.

The M3 Convertible features a Standard passenger-side exterior mirror that automatically tilts downward when the vehicle is shifted into reverse, improving the driver's rear vision. A tilt-down rearview mirror is Optional on the IS C.