The 2009 Mercedes-Benz SL grand-touring roadster gets more flamboyant front and rear styling for 2009 and gains some design cues from the classic 1950s "Gullwing" SL. There’s an edgier, more chiseled look in front, with composite lamp fixtures that flank the new grille design and sweep around into the fenders, and in back, the styling is a little neater. It’s similar to what’s being phased in throughout the Mercedes-Benz lineup, while much of the rest of the SL’s softer lines are carried over. Meanwhile, functional side-fender air gills behind the front wheels serve as nods to the past, and (on non-AMG models) the hood has been redesigned to gain two prominent "power domes." Other changes, as described by Car and Driver, include “larger side mirrors with curious arrow-shaped turn signals and, in the case of the SL550 and SL600, a faux air ‘diffuser’ and trapezoidal exhaust tips at the rear.”
These changes didn’t sit so well with some reviewers, who lingered on the idea that the 2009 Mercedes-Benz SL has gone many years now since a complete redesign. Car and Driver emphasized that the hood bulges do not correspond to “anything that gives the car more power,” and regarding the new front end, while Leftlanenews.com said that the rear styling looks dated, Britain’s Top Gear said that styling continuity was lacking: “Trouble is...they’ve grafted a square face onto rounded flanks, and it sits uneasily.”
The changes to the already elegant and sporty interior have been limited to a redesigned instrument cluster and steering wheel, and few reviewers had much to say about it. Leftlanenews.com pointed out the ability to “customize the interior with up to twelve single-tone and ten two-tone combinations of leather and wood trim.”
Meanwhile, the AMG versions get enough styling for spotters to easily differentiate them from standard SLs. Differences include a lower air intake in front, a bolder grille design with reshaped headlights, twin power bulges for the hood, special side skirts, and a different rear fascia. “That you're in the AMG version won't go unnoticed by the impoverished who can only afford Porsche Boxsters,” said Road & Track.