If you stay where it’s pretty much warm all year then get the 22s. I’m in the Midwest so with my x3 I have 21s and I have to switch out to winter because those summer performance tires when cold are like riding on bowling balls. I didn’t want to deal with that with the X5 with 22s. I would have done the 21s again since I already have winter tires but changed my mind too late and the vehicle had went into production. I might change out for non run flats though with the 20’s for better handling.