Endless series of electrical and mechanical problems. Relay in the left front headrest, shorted and burned, processor that controls rear door lock failure, processor that controls stop lights failure, broken window switch, failed low pressure fuel pump, back up camera works only when it feels like it, windshield wipers come on on hard left turn, radio comes on on hard right turn, broken bolt in tailgate hinge, oil leak back of turbocharger, oil seal failure on oil intercooler in the v of the engine, engine shut down by itself but eventually restarted on two occasions. Navigation system is cumbersome, otherwise what's not to like. Several service reps have expressed that my problems are not unique to the my car. Various dealers the car's been to (breakdowns appear most frequently when on vacation), have been very helpful. Mercedes emergency roadside assistance was very helpful on an evening when the car refused to start - it's a good feature. Car has 100,000 kilometers (62,000 miles) on it at present. Fortunately I bought extended warranty for the car, and the repair bills now exceed it's cost.