In many respects, the GS 450h is a showcase of all the technology that Toyota Motor Company has in its arsenal. As well as its formidable propulsion arrangement, which includes a variable valve-timed engine and an ultralightweight boost converter, the car's performance features include a continuously variable transmission, regenerative braking, variable gear-ratio steering, and active variable suspension all as standard. Options include power-active vehicle stabilizer with Z-rated run-flat tires ($3,400) and Lexus's precollision system ($2,850).
Inside, our test model came with voice-activated GPS navigation with integrated Bluetooth hands-free calling ($1,900), a 16-speaker Mark Levinson audio system ($1,780), heated and ventilated seats, adaptive cruise control, an intuitive park distance sensor, and all manner of comfort settings in which to enjoy our eco-friendly consciences. All told, our tester rang up at $65,794. The cabin of the GS 450h is very Lexus. A 6-inch screen sits in the center of a wood-trimmed dash, and clusters of buttons everywhere give the driver and the front passenger plenty of opportunity to customize the ride to their own comfort levels. The GS 450h comes with 10-way heated and ventilated power seats, Bluetooth hands-free calling, and Lexus's six-disc in-dash CD changer as standard. Our tester also came with the optional voice-activated navigation system, adaptive cruise control, and the upgraded 14-speaker Mark Levinson audio system, which is impressive as much for its excellent sound quality as it is for its broad range of 3-letter functions: from its ability to play MP3 and WMA-encoded CDs to its ASP (automatic sound leveling) and DSP (digital sound processing).
In addition to its 5.1 surround-sound audio capabilities, the upgraded stereo system supports DVD video and video CDs, which can be played back via the navigation LCD screen.
Pairing our Sprint Fusic to the Lexus Bluetooth system took a little longer than it should have, thanks to the phone menu being accessed via the Information screen rather than the Menu button. Once paired, we found that voice dialing was straightforward and that the system was adept at recognizing our spoken phone numbers.
The voice-activated navigation system was equally challenging. As we found in our time with the 2006 Lexus IS 350, one cannot just hop into a Lexus and rattle off speculative commands as is the case with a Honda or an Acura. A list of specific voice prompts must be learned and used in conjunction with the correct screen for the Lexus voice command system to be mastered. After some consultation of the manual, we found that (when in the correct screen) the voice-recognition system was adept at understanding destinations.
One peeve that we have with the voice-recognition interface is the amount of time one has to input a voice command after pressing the steering wheel-mounted Talk button. After each push of the button, the Lexus pipes up with: "After the beep, please say a command," followed by a pause and the beep, which all takes about 5 seconds. Considering that the input of a destination can involve as many as five steps, this adds up to a large amount of wasted time.
When possible, we preferred to program destinations by hand using the touch screen, which we found far more user-friendly. The ability to find destinations by entering a phone number was a feature we particularly liked. When fully programmed, the navigation system works well with a variety of screen configurations showing high-resolution maps, accurate turn-by-turn directions, and an impressive refresh/recalibration speed.
The other main cabin-based tech system in the GS 450h is dynamic radar cruise control, which uses a radar-based sensor to enable drivers to set a vehicle-to-vehicle distance between themselves and the car in front. As with other high-end cars we've tested, the GS 450h has three settings for this function (long, medium, and short) to allow drivers to tail cars at their chosen preset distance. With the relevant distance setting selected via a rocker switch on the steering wheel, drivers then use the regular cruise-control stalk to set speed in 5mph increments.
In practice, we found the function more of a curiosity than a useful tool. Accustomed as we are to swift throttle response, the car's acceleration when under the radar's spell seemed to take an eternity. When the system acted to slow us down, engine braking was a little more noticeable, and on the occasion of a Toyota minivan cutting us off, the system beeped and flashed at us to inform us that our input was needed to avert disaster. However, we always felt the need to keep a foot poised over the brake pedal just in case, and found that the occasional dose of good old-fashioned pedal input was needed for us to keep up with the flow of the traffic.
Other comfort systems on the GS 450h include dual-zone automatic climate control with an air filter, keyless entry, a power headlight cleaner, and a power tilt and telescoping steering wheel. There's no doubt that the Lexus GS 450h is a hybrid: even if you miss the Hybrid logo on the rear footplate, the cabin instruments leap out to remind you that this is no ordinary leather-and-red-walnut-trimmed Lexus interior. After depressing the push-button start, the only clues that you're ready to go are the illuminated instrument panel--including a voltmeter in place of the tachometer and an LCD schematic involving a wheel and a battery--and the fact that the button has turned from red to green.
Silently trundling out of the parking lot on electric power, we felt like we were in a large, gentrified Prius. Like the Prius and the 2007 Camry Hybrid, the GS 450h uses Toyota's Hybrid Synergy Drive system, which, as a "full" hybrid system, enables it to run entirely on gasoline, entirely on electric, or on a mixture of the two.