Are there any longer term potential problem areas with the ownership of a petrol tiptronic Audi Q5?

I had a Mercedes 280 for over 12 years then downsized two years ago to a C180k (which I regret as its much more compact on the inside). Now my eye has alighted on a new Q5 (higher driving position, easier access).

I know nothing about Audi except its German built like the BMW and Mercedes which I have previously owned. I prefer to keep my cars for several years and need petrol (low annual mileage and too many short journeys, with only 1 or 2 longer trips a month) and an auto, so expect to achieve about 30mpg or even less.