I'm looking at purchasing a used A6 Avant or Allroad. The family need the boot space which is one of the reasons I'm looking at A6. However, I notice that the price is quite expensive when including quattro. Is quattro really worth the extra money ? I know it's standard on the Allroad but that's looking outwith my budget so reviewing the A6 Avant which is within budget, but the quattro model is making it more expensive. Is it worth stretching ? Hope you understand the dilemma and able to offer some help/advice ?