We leased the 2013 SL in June and completely satisfied with the car at this point. They did a great job making it as much like driving a conventional car, which my wife likes. We spent ab out a year thinking about how it would fit our lifestyle and could not think of a single instance were we would be "stuck" without a gasoline motor. I charges quickly with the 240 volt charger. The dashboard technology is great and easy to interpret.
Driving past gas stations. We save over $100 to $120 per month by driving this car. I know this because I download the driving history stats to an Excel spreadsheet from the car's Internet portal. Being able to find a destination and download it to the car (via an iPhone app) is great. The all around view works very well and makes it easy to park. I can get 75 plus miles with a combination of city and Interstate driving using Eco mode and enhanced regenerative braking mode. No problem driving 60 - 70 mph. Plenty of room for 4 and the seats go down easily to carry cargo.
Get rid of the back up alarm. All small late model cars are too quiet to hear in a parking garage so I don't see the point.