I have owned and driven a plethora of sports cars and find my 08 Sport package equipped RFT wearing X5 to handle quite well and take rough roads just fine. I suspect you may have an issue with yours IF equipped with the sport package. Even with "sport" off, when my wife drives, it seems to handle rough roads just fine. My neighbor has an E53 X5 and E90 M3 and agrees that the ride of my X5 is great. Maybe a trip to the dealer is in order?