Silly question... Get rid of the Run flats and buy the Michelin PSS. I'll be doing it as soon as I burn the rest of the life out of the Dunlops we're on now... And I cannot wait until that day!
If the lack of run flat worries you, buy a BMW Mobility Kit and throw it under the floor in the back.
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2018 F15 X5d Carbon Black/Nutmeg Individual- Oil Burner Tow Rig
2013 E82 1M3 Carbon Black/Black- S65/DCT Track Toy
2013 F25 X3 35i Alpine White/Chestnut- German American Family Hauler
Past: '11 E91 335is, '11 E90 M3, '10 X5M, '14 328d, '03 330i Dinan3 ZHP, '04 330i ZHP, '12 X3 35i