I know this is an old thread but here is my opinion:

Yours is W204 C200, surely came with M271 engine like mine, W203, C180, year 2004. Our engine is similar, 1.8 kompressor. Mine already clocked 136, 000 km without any problem. Yeah, its a low mileage car and I really love it. Other spec might be different, but surely our engine are similar.

As others, you've got a lemon unit. Hope that your problem is solved now.

For my car, I change EO at every 15, 000 km or 1 year AND I only use mobil1 0W40. Pls use this and its true that my normal service cost no more than RM 500, even when I have to change the oil filter.

I never received any top up engine oil messages so far since I bought the car in 2012. Unlike others, the message is normal which made me even love my car more. Can u imagine, one year interval, no such message appeared. I always use the car for long journey, penang - melaka, penang - pahang.

To those who bought a recent MB car, the official service interval is now at every 25, 000 km/1 year. This is even better especially when out of warranty. Just remember to always use the best EO.