You could say Mercedes-Benz has a two-fer. There's the drop-top true SL sportscar, for those who don't mind paying a base price just a shade under six digits for the entry level privilege. Then there's the SLK vanishing top roadster for just under half the price - sort of sports car light.

Call it a Madonna to a Britney Spears comparison, maybe? Both blonde. Both brash. Both tradition-shattering trendy in a volatile, voluptuous way. We'll add a towhead Gwen Stefani to the mix, rock solid with just of touch of brash, for stability. They all wear stars on their dressing room doors, although not the three-pointed variety that anchors the nose of every Mercedes-Benz. (We always think of M-B vehicles as coming in some shade of silver, so "blond" seems like an natural extension.)

The SL roadster gets the major upgrade for 2007 as SLK moves into the third year of its current iteration. Both sport the latest darling of the sports car world - a retractable hard-top that coverts to open air in a mater of seconds. Push a button and go from coupe to uncovered faster than Demi Moore dropped her top as yesterday's floozy in the widely-panned (title) flick.

SL, of course, is the real heavyweight of these siblings, and sports some exterior changes, including such trim items as front grille, clear lens taillamps, and chrome trim surrounding the fog lamps. A new 5.5-liter, 382-horsepower, 32-valve V8 thunders under the hood of the higher volume, performance SL550 guided by a seven-speed automatic trans. Check in at $95,575 for starters and go up from there.

Junior grade SLK's main contribution, besides quick change artist, is a value-packed 280 version, with 228-HP, 3.0-liter V6 power for a comparatively modest $43,350 entry price. Inside it's dominated by large chronometer-style gauges, with silver-colored switches of course. Earlier SLK models had merely a rear windscreen at head level to keep top-down chilling breezes under control. Cold shoulders get a warmup with the current headrest warm air heating system, called AIRSCARF.

Obviously, M-B aims to please all audiences.

Roadwise, the SL550's 14/22 mileage rating qualifies it for a gas guzzler penalty tax. However, the SLK 280's 20/27 MPG doesn't. (We'll leave the exotic, extraordinarily powerful SLK AMG and SL55 AMG for a separate interpretation. They're a whole class of blondes by themselves.)