Mercedes Benz ad...and tech question

I came across a Benz advertisement which boasted about how the diesel powered e-class ran 100,000 miles, non stop. At first, that sounds really great. Granted, I know it probably had to stop for gas and tires somewhere in there, but never the less, it makes for a good ad.

Now here is my tech question...is it harder on the engine to run that distance with only a few periods of pulling over for gas, or is it harder to make the same distance with real world variables such as temperature changes due to various seasons, stopping and starting, etc.?

I have heard that MB makes some of the better 'everyday' engines in the business, but are held back by only their electrical problems?

What do you say?

Thanks,
Chris