[quote=sirees01]Does anyone have experience of the 21" style 239 wheels on the X5.
I do have Adaptive Drive on my X5 but I am wondering if the change from ML with 19" wheels & Air Suspension will be severe?quote]

I have 21" 128's with adaptive drive. So while not the 239's they should give a similar ride.
I find the ride fine and leave adaptive drive on sport as I can't feel much difference in terms of ride feel, but the car feels a lot more stable in the bends when in sport. I have test drove one prior to my purchase with has 20" wheels and could not feel the difference. Only thing I would say is the wider tires cause the car to tram line a bit on really bad roads but most of the roads near me are in pritty good nick