Bentley GTC // The British Bentley marque is reborn since its acquisition by Volkswagen, and the GTC Speed is its most powerful convertible ever. Based on the gorgeously muscular Continental GT coupe, the standard GTC’s 6-liter twin-turbo W-12 pumps 553 ground-pounding horses through a 6-speed automatic transmission, and the GTC Speed ups that to 600 ponies and a not-in-my-neighborhood 200-mph top end. You can have it with dark or bright turned-aluminum inserts to set off its diamond-quilted, leather-lined cabin. $202,000
BMW Z4 // Some deemed the previous Z4 ungainly, but this svelte new one closes that discussion. In addition to a choice of 255-hp or twin-turbo 300-hp 3.0-liter 6-cylinder engine under its long, low hood, it offers a slick aluminum hardtop that retracts in 20 seconds and occupies minimal space in its 9.2-cubic-foot trunk. Choose between 6-speed manual or automatic and from a range of powertrain and suspension settings available through the standard Dynamic Driving Control. $50,000
Cadillac XLR // Today’s retractable hardtop XLR includes the ultra-luxury Platinum and the ultra-hot XLR-V. The former packs a 320-hp 32-valve DOHC VVT Northstar V-8, the latter a hand-built 443-hp supercharged version. Both feature Magnetic Ride Control, Adaptive Forward Lighting, hand-cut and sewn leather with wood or metal trim, and a suede-like Alcantara headliner. $87,000
Chevrolet Corvette // In 505-hp Z06 and 638-hp supercharged ZR1 form, the Corvette offers super-car capabilities at reasonable prices, while even the basic 430-hp convertible optimizes its grins-per-dollar ratio. Variable-ratio power steering and a rear-mounted 6-speed manual gearbox are standard; 6-speed automatic, a power top, custom-wrapped leather, and Magnetic Ride Control are optional. $54,000
Infiniti G37 // Infiniti’s first G convertible adds open-air cruising to Nissan’s luxury brand. Like many modern drop-tops, its three-piece steel roof folds into its trunk. Unlike most, it boasts a Bose open-air sound system that dynamically changes equalization based on speed and ambient noise and adaptive climate control that adjusts accordingly. Both models are well motivated by a 325-hp 3.7-liter V-6 driving a 6-speed manual or 7-speed automatic. And the G37S Sport 6MT adds performance steering, brakes, and tires. $46,000
Lexus IS // Leave it to Toyota’s luxury Lexus brand to launch a rear-drive, entry-luxury retractable hardtop convert- ible at the same time Infiniti does. Also, to offer the same new pair of convertible-enhancing features: audio and climate systems that automatically adjust to vehicle speed and top position. Two V-6s are available: a 204-hp 2.5-liter and a 306-hp 3.5-liter. Stability control is standard, and the three- panel roof disappears into the trunk in 21 seconds. $40,000
Mercedes-Benz SL // Mercedes’ SL sports car heritage began with the 1954 300 SL Gullwing coupe and the first ’57 SL roadster. Today’s SL, aggressively redesigned for 2008, offers several performance possibilities, beginning with the V-6 SL 280 and SL 350, extending through the V-8 SL 550 and V-12 SL 600, and culminating with the 604-hp twin-turbo V-12 SL 65 AMG. Available AIRSCARF neck-level heating extends top-down comfort into the cooler months. $98,000
Ford Mustang // Ford’s red, white, and blue Mustang has been America’s favorite “pony car” since 1964, and this redesigned 2010 iteration boasts power, safety, and technology features, a tautly sculpted exterior, a precision-crafted interior, and a retuned suspension. With standard AdvanceTrac Electronic Stability Control, the base V-6 convertible starts at $27,000. (The 315-hp V-8 GT at $34,000, and the 540-horse supercharged Shelby GT500 at $51,000).