Looks like Pirelli makes an all-season option in the 275/315 22" size. They are Bentley spec, and quite expensive, but basically the only all-season option for that size. I spoke with a TireRack rep, and as far as the specifics of what make the tires "Bentley Spec" it seems the Noise Cancelation is the main additional feature. Otherwise he said there should be no issues running them on the X5. Has anyone had any experience with these tires on their X5 in this size?
https://www.tirerack.com/tires/tires...0Sport%20Brake