I would have to say that the age kills the value more than miles, but only to a certain limit.
For example, my 2005MY (but built in Oct 2004) X-Type has only 67'000kms and is worth less than a 2007MY car with 100'000kms, with the exact same spec.
But if the milage climbs higher than the psychological 100K mark, values start to drop dramatically...
No need to mention that car prices (new & used) in Switzerland can only be described as taking the