Once one of the world's greatest carmakers, Cadillac has seen more ups and downs over the past few decades than Apple's stock price. However, GM's wreath-and-crest division has made a concerted effort in recent years to reclaim its former glory. Rather than allow European and Japanese automakers to rule the luxury-brand roost, Cadillac has decided to tackle its competitors head-on. A key part of this effort is the company's halo car, the 2009 Cadillac XLR-V.

As the ultrahigh-performance version of the XLR two-seat retractable hardtop roadster, the XLR-V serves notice to European automakers that they don't have an exclusive hold on sexy drop tops with blistering performance. The XLR-V also boasts the requisite six-figure price of admission. Subtle hints such as 19-inch wheels, a mesh grille and quad exhaust tips clearly signal that this is no ordinary XLR. Backing up the "V" badge is a hand-built, supercharged 4.4-liter V8 that cranks out a lusty 443 horsepower, along with firmer suspension tuning and upgraded brakes.

With its muscular engine and Corvette-based platform, one would expect the Cadillac XLR-V to be a strong performer. Sure enough, its ripping acceleration leaves lesser luxury roadsters behind, and its handling and braking are more than respectable. Yet its relatively uncommunicative steering leaves us cold, and its handling still isn't as sharp as what you'll find in the European competition. As such, the XLR-V is far from class-leading in the driver entertainment category.

A couple other minor shortcomings prevent the XLR-V from taking the title of top luxury roadster. While the cockpit looks luxurious, it doesn't fit drivers of all heights. Moreover, while most interior materials seem appropriately rich, a few others are decidedly average. In this exclusive segment, every detail counts, and the XLR-V can ill afford such missteps.

The luxury-roadster class includes such luminaries as the BMW M6 convertible, Jaguar XKR, Mercedes-Benz SL-Class and Porsche 911 Carrera Cabriolet. Of these, the Porsche offers the most rewarding drive, the M6 allows seating for four and the Mercedes arguably provides the best combination of luxury, style and performance, especially in AMG form. The 2009 Cadillac XLR-V is an interesting domestic alternative, and it may even turn more heads than the other cars due to its relative scarcity. But if it were our 100 grand, we'd take the Porsche or the Benz.

The 2009 Cadillac XLR-V is a two-seat luxury roadster. Its retractable hardtop can transform the car from closed coupe to wide-open convertible in less than 30 seconds. Nearly every imaginable luxury feature comes standard, including a nine-speaker Bose stereo (with satellite radio), OnStar telematics, a navigation system, Bluetooth connectivity, keyless entry and start, xenon headlights, adaptive cruise control, a heated steering wheel with power tilt and telescope adjustments, a head-up display and rear parking assist. The lone factory option is a set of chrome-finished wheels.

A supercharged 4.4-liter V8 sends 443 hp and 414 pound-feet of torque to the 2009 Cadillac XLR-V's rear wheels. Power is channeled through a six-speed automatic transmission with manual-shift capability. We timed an XLR-V from zero to 60 mph in a scant 4.6 seconds, which puts it more than a full second ahead of the standard XLR and right in the thick of the high-performance roadster race. Braking performance, at 119 feet from 60 mph, is adequate, though the top stoppers can do the deed in under 115 feet.

Antilock disc brakes, traction control and stability control are all standard on the 2009 Cadillac XLR-V. As in all convertibles of this ilk, the XLR-V's side airbags inflate to protect both the head and torso.

With a jump of 123 hp and 114 lb-ft of torque over the standard XLR, the 2009 Cadillac XLR-V is vastly more responsive. Lean into the throttle and the XLR-V catapults forth on a wave of supercharged torque. Even with its firmer suspension setup, though, the XLR-V is still tuned more for boulevard cruising than all-out handling, which means it feels softer than some more focused rivals. This attribute conspires with the rather heavy and numb steering setup to make this performance roadster feel a little out of its element on winding roads.

However, in normal driving, the XLR-V feels swift and stable. Cowl shake is nearly nonexistent and the V8 sounds terrific. Wind buffeting can become somewhat intrusive with the top down, but the XLR-V is whisper-quiet with its top up.

The cockpit of the XLR-V offers much to like. Its design is appealingly simple, the leather supple, the wood trim convincing and the build quality solid. However, we find the XLR-V's cockpit less appealing in light of the car's price. The switchgear looks and feels pedestrian, and some trim pieces have a tacked-on appearance. As in many cars of GM origin, too many functions have been crammed onto the turn-signal stalk. In addition, the steering wheel's a bit large for our tastes, and the limited rearward seat travel may cramp the styles of taller drivers. The trunk boasts a respectable 11.6 cubic feet of space when the top is up; top down, however, that number drops to just 4.4 cubic feet.