Out of all of the abovementioned cars, Bmw would be my choice, its solidly built and roomier than an A8(used to owned 54plated 4.0tdi),servicing would defo be cheaper for the BM too.
10k jag would probably cost you an arm and a leg to run, Mercs quality had deteriorated over the years(although recent models have improved somewhat...)
However, if the badge on the bonnet is not a priority, I would go for brand new Honda diesel or a Toyota Prius, both cars very well built and cost bugger all to run.
