I know nothing about the dealer or the truck but I might be able to answer your last question. I think that you should take the A8 rather than an 80 on your trip across europe. I have used my 80 a fair bit this weekend and it is not exactly quiet and refined when compared with my Volvo. Well thinking about it you will not be travelling at speed when towing so wind noise is less of an issue, but its still there are 60mph

The seats in the 80 are not as comfortable as more modern luxury cars, maybe its just the GX but they are not even close when compared with my Volvo. I'm sure your family would prefer the comforts of the A8 compared to an 80.
It's not like you are travelling to remote uncivilised places so reliability is not much of an issue here. I would assume as its your car the A8 is in top condition so it's unlikely to give up the ghost 2k miles from home. Even if it does I'm sure most garages can fix it as they all have code readers these days. Also I'm sure you can find some very useful software here
http://garageforum.co.uk/forum/149-vag-group.html which will enable you to do most things on the A8 with the right cable and a laptop. I would not even bother with a tool kit on a car like that for travelling around Europe as you would not be able to fix it anyway without the right parts.
The 80 is a great second car IMO, would not have it as my main car as mine does not fit into multi-storey car parks (an unmodified one will tho...) Not really sure where I am going with this

I think what I am saying is that you should get an 80 but not for towing the caravan across the continent, clear as mud?

Petrol heads never make rational decisions when it comes to cars, chances are you will end up buying it and we will take bets on what you end up doing with it
