Nice car, purchased it for the Diesel engine and 6 passenger capacity. Overall, experience has been poor during and out of warranty. Engine stopped completely at highway speed on 3 separate occasions. 1st time was fuel pump, second time fuel sending unit and third time was crankshaft sensor. Seems like this model has problems with electrical (replace light bulbs every 2 - 3 months), airmatic suspension goes into error mode. We have spent over 6K$ in repairs since the car has been out of warranty. Unfortunately this is one purchase decision that I regret making.
Seating for 6. Fuel consumption for a large car is good.
Quality, reliability. Mercedes needs to fix the problems once out of warranty if it looks like they are related to a problem you encountered multiple time under warranty. It's very expensive to fix once you pass the 50K miles compared to our other MBs.