Just a heads up if your have problems losing tyre pressure. The dash warning came on so i checked the pressures and found 3 tyres were low on pressure. Thinking I must be unlucky to get 3 punctures on run flats I checked the valve cores. All 3 were not tightened correctly! I tightened them and thought all would be good but one tyre kept tripping the warning every 10 days or so. I kept topping up the air until the car went in next week but last night when washing the car I could see air bubbles around the valve body. I took it to a local tyre place this morning and when they removed the valve they found a piece of cloth stuck under where it seats in the wheel! Probably a one off but may be worth checking your valve cores as this is obviously not getting checked.