Hello, ride the Conti TS 850P since 4 winter (50,000 km) Now I have measured the profile depth to see if there is a change. Profile depth (see also picture) Outside: 4mm Center: 6mm Inside: 5mm Which value should now be decisive for me? And if we are there which would you take (BMW 520D F11 rear wheel) – Goodyear Ultragrip Performance Gen1 (480 Euro) – Conti WinterContact TS850P (550 Euro) – Michelin Alpin 5 (590 Eur) Thank you