I took these tyres off my B7 RS4 Avant about a month after I bought it, and I believe they had been on it for the previous 6 months. They're Dunlop SP Winter Sport 3D, sized 275/30 R19s. Tread depth is 4.5-5mm on the 2 that had been on the rear, and 3.5-4mm on the two that had been on the front wheels. The inside edge of one of the fronts was worn more than the others (alignment issue corrected when I replaced them).
I'm open to sensible offers for collection in the Reading area.