Problems that cannot be corrected must be safety related, or limit your use of the vehicle. All you need to do is show that it is not normal. Take pics of a bunch of other X5s that don't have this problem, and yours. Talk to BMWNA for help in getting it fixed. If it is normal, fine. IF it isn't (and your pictures should show this) have them fix it. I don't think it would bother me much unless it was obvious. I assume no one will notice it.