M ercedes-Benz SL convertibles are the preferred ride of Beverly Hills desperate housewives. But if you see the letters AMG on the rear, you're looking at no chick car but a beast upgraded with all manner of motor-sport love. The 2009 SL63 AMG convertible hit the streets in May. Like all SLs, this new one traces its ancestry back to the still-coveted '56 300SL (the open version of the classic Gullwing coupe), and is hands-down the best-handling SL in half a century.

Tested on mountain twisties North of Palm Springs, we found the SL63 exhilarating, a wolfish supercar in sexy sheep's clothing. Why turn the radio on? The engine's exhaust note is all the music you'll want to hear. We love the F1-inspired Race Start launch control, which lets you hammer from zero to 60 in 4.4 seconds. The car is electronically limited to 155 miles an hour, but if you option the AMG "killer chip," you can kiss 190 miles an hour with the top down.

The fun starts with a gutsy, AMG-exclusive, 518-bhp, 6.2-liter V-8, linked to a seven-speed MCT (multi-clutch technology) gearbox. A discrete dial alongside the console shifter offers a wealth of transmission settings. Select from C (comfort), S (sport), S+ (seriously sporty) and M (manual) to dial your shift speed. The 200-millisecond C-setting is fine for heavy traffic, but you'll prefer to play in sport, with shift times that are 20 percent quicker. S+ is 40 percent faster still, and for serious driving, the manual setting holds your selected gear all the way to the V-8's snarling 7,200 rpm redline, unless you shift first (paddles, naturally). For downshifts, a lightning-quick automatic throttle blip minimizes shift shock.

Did we mention those huge (14.2-inch front/13.0-inch rear) cross-drilled brakes? Looping through the California mountains, we put them to the test and felt the G-forces hurl us into our seatbelt. Stopping power is not lacking, trust us.

The new SL's restyling is subtle but slick. The metal roof hides in just 16-seconds, and M-B's clever Airscarf system (first seen on SLK roadsters) lets you run topless in any weather. If you live in 90210, your wife will love this car, but you'll hide the keys. It's that good.

Sticker: $133,000
More info at mbusa.com