Executive derision

Could you please help? I have to decide on the best model of executive type car for very high mileage all year round use, and it must be German. Use includes 4am early morning starts and late return from all over the UK (even Scotland) in all weathers. Therefore safety and handling in adverse weather conditions is a major factor. Could you please give any comments regarding this and generally about:
New BMW 520d (rear wheel drive) 5*NCAP rating?
Audi A5 2.0 TDI (front wheel drive) Just above entry level.
VW Passat CC (front wheel drive) Has most of required extras as standard.
I have heard negative reports regarding the BMW in ice and snow and drivers having to weigh down the boot to aid traction, which obviously concerns me. What do you think? From a BIK point of view I think the above models are comparable. I have to make a decision pretty quickly and would appreciate your response and comments.

Asked on 14 August 2010 by AB, via email

Answered by Honest John
Has to be the F10 BMW because it's chain cam and a new model. It just achieved a sensational NCAP rating. 520D best on 16” wheels, not on silly (for a 520) 19” wheels with low profile tyres: www.honestjohn.co.uk/carbycar/bmw/5-series-f10-201.../
Test and video:
www.honestjohn.co.uk/road-tests/bmw/bmw-f10-5-seri...s
The A5 and Passat are both belt cam.
Test and video of A5Sportback:
www.honestjohn.co.uk/road-tests/audi/audi-a5-sport...t
For winter, buy a separate set of wheels with winter tyres and fit them
from March to November. You will be wearing out tyres anyway, so the only real extra cost is the cost of the wheels.
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