I just installed style 215 wheels on my 2009 X6 and decided to give my style 258's as hand-me-downs to my 2001 X5. The only requirement was to install the hub centric rings (purchased at Discount tire for $5/for set of 4) on the fronts as the X6 has 74.1mm bore on the front wheels and the X5 requires 72.5mm (rears don't require the hub centric rings as they are 72.5mm). I was initially worried about the offset difference on the rears but after installing think it is a perfect. I would recommend installing them to see how everything fits/looks and go from there. To do a test install as to determine how it looks you do not need to install the hub centric rings on the fronts but would not recommend driving any distance/speed without them.