Talking about tread wear, am I right that on Torsten Quattro models tyre wear Will be roughly equal on all 4 tyres since on ordinary day to day driving, power is equally split between front and back? Obviously on 2WD models the front tyres get worn out quicker.
2mm on the fronts, best double check the inside edges of those front tyres by the way to make sure they haven't worn to the cross ply. Mine had before they got to 2mm
For reference, the handbook states "On vehicles with four-wheel drive, all four tyres must have the same rolling circumference. Also avoid using tyres with varying tread depths". Check the index for quattro for the page number but it's p174 in mine.