(excerpt from SC430 vs. SL500 vs. XLR comparo) 2004 Cadillac XLR The 320-horse XLR does 0-60 mph in an impressive 6.25 seconds. From now on, people are likely to talk about Cadillac as "pre-XLR" or "post-XLR." While Cadillacs in the past decade have showcased styling or performance or technology, the XLR is the first model that fully and successfully integrates the automaker's ambitious forays in all three directions. The result is a unique and flavorful "new Cadillac," a car in many ways unlike anything else on the road. The numbers speak volumes. Compared with the SC and the SL, the XLR has the longest wheelbase by almost three inches--yet, thanks to snug overhangs front and rear, it's the shortest in length. The XLR is the widest and lowest, and it's a good 200 pounds lighter than the Lexus and 400 pounds lighter than the Benz. Engine output, 320 horsepower at 6400 rpm, is the best of the trio. At 24 mpg, the XLR delivers the best EPA highway fuel-economy rating, too. That David Hill, vehicle line executive for GM's Performance Cars, presided over development of the XLR is telling: Hill is also chief engineer for the Corvette. In fact, the XLR is based on the same next-generation architecture as the forthcoming C6 Vette. Composed of steel hydroformed frame rails, an aluminum cockpit structure, and composite floors with balsa-wood cores, this advanced structure is lightweight and exceptionally stiff. The XLR's DOHC 32-valve 4.6-liter V-8 is the first Northstar to be used in a longitudinal rear-drive layout. To make it fit, the water pump had to be moved to the front of the engine--a seemingly innocuous change that necessitated reworking all the V-8's water jackets. "We completely redesigned the block and heads," says John Zinser, GM Powertrain Northstar chief engineer. The XLR V-8 also incorporates such Northstar firsts as electronic throttle control and variable valve timing. The XLR's transmission, a five-speed automatic, is mounted at the rear for improved weight distribution. It includes a semi-manual sequential-shift feature that allows the driver to change gears simply by nudging the lever fore or aft. The XLR interior is graced with superb leather buckets, handsome eucalyptus-wood insets, and patterned-aluminum accents. Almost every imaginable convenience is standard, including GPS navigation, heated and cooled seats, a voice-activated telephone, a spectacular Bose stereo with additional headrest speakers, and gauges designed in concert with famed Italian jeweler Bulgari. The only option is an XM satellite radio. The XLR includes a head-up display that projects basic instrument information onto the windshield and works more effectively than any we've seen before. Shift into semi-manual transmission mode, for instance, and your chosen gear conveniently materializes alongside the digital speedo that normally appears by itself. Like the SL500, the XLR features an adaptive cruise-control system that uses a forward-mounted radar unit to maintain a selected distance between you and the car ahead. And while a keyless ignition system is optional on the SL, on the XLR it's standard. In fact, the XLR is truly keyless--there are no key holes in the doors or the ignition. Simply pocket the key fob, and you can open the doors or start the engine at the push of a button. (Cadillac does include a key in case of a complete electronic failure--there's a small keyhole hidden in the bodywork.) At the test track, the XLR proved true to its performance-car pedigree. Fastest to 60 mph (6.25 seconds), best 0-100-0 time, and second best on the skidpad (0.83 g) and in the slalom--despite relatively skinny all-season run-flat tires. Pushed hard on the road, the XLR makes thrilling noises as the Northstar nears its 6700-rpm redline, and the suspension returns a remarkable combination of handling quickness and fluid ride control. Credit the XLR's magnetic ride-control system, which automatically adjusts shock damping to handle changing road conditions and driver inputs. Asked if Cadillac has any plans to introduce a rumored sport package, XLR chief engineer David Leone replied simply, "We think the XLR is where it ought to be right now." As chiseled as a stealth fighter, the XLR is as high-tech as one, too--featuring a head-up digital-instruments display, magnetic-electronic active suspension, keyless operation, and a central touch-screen. The XLR's folding top is the slowpoke in this group, but it still needs fewer than 30 seconds to work its hardtop-to-roadster magic. Conclusion We remain impressed by the uncompromising quality and finesse that's evident throughout the Lexus SC 430. Many spas aren't this relaxing. Yet the car leaves us hungering for more flavor and driving excitement. This isn't an automobile that'll inspire you to sneak to the garage at night just to smile at its lines. Nor will its ultra-competent moves set your synapses afire. The SC, instead, is the ultimate in splendid isolation--and more than 14,000 buyers annually couldn't be happier. It's difficult to conceal our admiration for the Mercedes-Benz SL500. Few automobiles do so many things so well--or look so good doing them. From its timeless lines to its Pullman-car cabin to its effortless, exhilarating performance, the SL stirs the senses even as it soothes the soul--a remarkable achievement that justifies its steep admission price. Status is obviously a huge purchase consideration, too: for many shoppers in this imperial market niche, only the three-pointed star will do. Yet here comes the Cadillac XLR, a car brimming with personality, performance, and astutely integrated, leading-edge technology. Does it take the crown from the SL500? Final answer: not quite. The SL has ingot-like fit and finish, and it radiates a poise and sophistication that, frankly, we'd expect of a company that's been building SLs for half a century. Yet that only emphasizes Cadillac's achievement. The XLR is a world-class roadster that, right out of the box, is nipping at the heels of one of the most legendary two-seaters in the business. Factor in the XLR's $10,000-plus price advantage, and it's a safe bet that Cadillac should have no trouble selling the 5000 or so XLRs it's aiming to build this year. For now, the Mercedes-Benz SL500 remains on top. But the arrival of the Cadillac XLR proves an age-old adage: It may be great to be king, but you're never safe on the throne. Just ask Elvis.