W211 ... are they any good?

I have been offered a 2005 E200 Elegance with 28,000 miles on the clock. Its genuine as the paperwork that comes with it is quite comprehensive. It is spotless inside and out and to be honest I quite fancy it. It will be for 'the lovely lady indoors' as her run around and will probably cover mileage as high as 100 a week !! The price is also quite attractive at way, way less than €10,000

So my question is .... what goes wrong with these cars? What little surprises would be waiting for me if I buy it?

Thank you in advance ....