Despite a couple of mechanical issues I love my A6 Allroad. Great car to drive, quiet, comfortable and the engine pulls like a train.
I regularly tow a caravan and had had no issues. Its very stable when towing the 'van. On occasion I have also towed trailers full of logs and builders rubble right up to the 2500kg towing capacity. Again I have had no issues doing this.
The only issue I have with the car is the boot isn't really that big with the rear seats in position.
I find I get 35 - 38 mpg and I live in a rural area with no motorways/dual carriageways so its mostly A-roads and twisty/turny B-roads.
The car handles great in all weather conditions and on the odd occasion there is snow it feels safe as I fitted a set of Vredestein 4-season tyres .