I love the dashboard design of this S-class. However, those gauges are completely virtual, displayed on a blank LCD screen; if the screen dies, I will have no functioning gauges. Bad design, in my opinion.

The "4Matic" badging denotes all-wheel-drive. Normally the badging would also be outside, but on this particular car, the "Bluetec" badging for the diesel engine already takes up the space where the "4Matic" badging would otherwise go. Mercedes-Benz, for 2012, is making 4Matic mandatory on some models, including the S350 Bluetec and the E550.

This generation of the Mercedes-Benz S550 (chassis W221) launched in the US with two models - the mainline S550 and the super-expensive S600. Eventually other models were added, including the S400 Hybrid and the S350 Bluetec; both models cost a bit less than the S550 while delivering better fuel economy.

The S350 Bluetec is part of a new generation of clean-diesel German cars meeting California's stringent emissions regulations. These German cars use AdBlue, a proprietary urea solution, to reduce the nitrogen oxide emissions; AdBlue is slowly used up over time, so it needs to be refilled once a year. These vehicles also need the low-sulfur diesel fuel that is common in Europe but was unavailable in the US until 2007 or so.

In the US, diesel-powered cars have limited appeal, partly because only selected gas stations have diesel, partly because diesel fuel often costs much more than gasoline (wiping out the diesel fuel economy advantage), and partly because the late 1970s General Motors diesels, hastily converted from gasoline power and notorious for engine failures, had left a bad taste in the motorists' minds.