i have a 04 allroad and its been awesome for the last 4000 miles. before i had tha AR, i had a 02 A6 2.7t which also had no problems (its basicly the same car, less the suspension and the trunk). you should have any problems with it. audi usually stands by their cars very well. mines a lease and my dealer takes care of all oil changes and any service needed - even washer fluid, wipers, etc.
as far as the car itself, its sweet. i have the 2.7t and it pulls awesome. keep us posted