I am commenting on the 2015 model, adding a few comments to what others have already said.
-Does it have back up sensors?
Yes, "Parktronic" works well. Visual and sound based. This is different from a backup camera.
Also, both left and right side mirrors tilt when backing up during parallel curb parking.
Both side mirrors dim slightly when someone follows you by night.
-Charging timer:
None on board. Get a programmable (delay timer) EVSE, like Siemens Versicharge, or one of the Jesla juice box models.
-Electronics:
Nice 8'' display. Simple interaction via button on middle armrest. Navigation system, traffic information, and maps are good. The radio and sound quality are excellent. iPhone connectivity satisfactory.
MB's iPhone app is terrible.
Blind spot assist is a nice but not mandatory feature.
-Driving and range:
I find both great. "range o meter" is conservative. See multiple other posts on this forum. Comfortable driving and good manoeuvring. I find torque and acceleration great.
-Interior:
Well finished and comfortable fully adjustable seats, armrests, doors.
Well designed storage (sun glasses, cup holders, door pouches, storage boxes under seats where your your knees go around the seat, glove compartment,
AC consumes less electricity than the interior heating or heated seats consume.
MB's adjustable "star vents".
Rear seats headrest are a pain.
-Trunk:
Adjustable level of trunk floor.
Handle and pretty light pull down of trunk rear trunk flap.
When folding down rear seats, the trunk area becomes almost flat and level with charging items from the rear.
-Noise level:
This seems to be more a poor insulation problem of the noise you hear from surrounding cars, than the "sound" made by the BCED itself. A lot of the outside noise appears to penetrate through the joints or windows on side doors. Generally sound insullation degrades as a car ages, so we'll hear/see how the BCED sounds in 3 years from now.
There were some posts on replacing the default RFTs with regular tires, improving overall comfort/noise level.
There is no moon roof or sun roof, in case this is something you want.
The BCED is an EV only. No backup gasoline engine.
The BCED is my first electric car. So I may sound more thrilled than other EV drivers. The BCED is an elegant car, MB styling and goodies.
Over the past 9 months I learned a lot more about the car by reading the electronically available manuals, search the web, look at pictures, actively read posts on this forum, than talking to any sales person at a MB dealership.
The MBUSA customer service phone line has been helpful with answering specific and direct questions. They are generally helpful and all my phone calls had a positive outcome.
They do a good job.
I am spotting more BCEDs in the SF bay area now (July 2015), than I saw in March 2015.
Good luck!