A lot of factors particularly driving behavior can affect how these engines respond to fuel grades, but Audi recommends premium in most of its 2.0 TFSIs - I say most because there are a few FlexFuel engines that are tuned for mid grades or "regular" or even E85. The Q3 does NOT have this type of engine. I run premium all the time as it burns cleaner and provides peak rated power - for me a point of driving. The extra 10 cents a gallon doesn't motivate me to risk potentially higher maintenance costs later or for the next owner - just my 2 cents ...