Which car is capable of covering high mileages reliably?

I am an equine veterinary surgeon doing over 40,000 miles a year. My Saab 9.3 2.2-litre diesel has come to the end of its life at close to 300,000 miles. What do you suggest to replace it? I always buy secondhand and run cars until they die. Would a Ford Mondeo, Skoda Octavia or Vauxhall Omega be as reliable if I cannot find another Saab? Other suggestions would be welcome.

Asked on 19 January 2013 by JW, Warwick

Answered by Honest John
I'm very happy indeed with the 64mpg I am getting out of a BMW F30 320dED. It feels very solid on its 205/60 R16 tyres, but in all honesty I cannot tell you how long it will last. Another car that felt impressively solid was a base mode Mercedes-Benz C200 CDI Classic SE manual. That felt like it would do a million miles over 10 years.
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