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The wear on the inside of the tyres is pretty much 'standard' form due to the way BMW set the geometry up on the X5s I'm afraid.
They need to camber to make the big ol' trucks handle!
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This is not quite true...
I learned a valuable lesson on my first X5 (E53 - with 20's) about how the BMW default settings can ruin the inner edge of the rear tyres, and can lead to wear on the outer edge of the fronts - especially if they set your car to the wrong extreme of their range of adjustment.
Even though mine was a BMW Approved Used car I noticed I had excessive wear on the inner edges of the rears after a few thousand miles. Fortunately I caught it early enough.
I use
http://www.wheels-inmotion.co.uk/ in Chesham for all of my cars - they are very knowledgable, and spend the time to discuss what you want to achieve.
They found that my E53 was set within BMW tolerances, but it was clear that this was still causing uneven wear. They reset my car within BMW tolerances, but at the other limit such there was less camber and therefore even wear. I was also able to swap the rear tyres left to right (directional tyres, so this involved taking the wheels off the rims).
It can be done, and it definitely did not affect the handling.
Likewise with my current X5M, as soon as I could I got it looked at by WIM. Once again it was within BMW tolerances and it was clear just by looking at the camber and the wear pattern on the tyres that I was going to waste a set of tyres.
This time I got Wheels in Motion to make an adjustment just outside of the BMW range in order to further preserve my tyres without compromisisng my handling. They are able to adjust a number of parameters (although not the front camber) in order to achieve a decent overall balance.
I was careful to give the car a decent spirited test drive before and after, and once again I can categorically state that the handling was unaffected.
Rather frustratingly a defective driveshaft had to be replaced by BMW immediately after this, and BMW perfromed a KDS on the car. I had to go back to WIM to have it checked and adjusted. Interestingly BWM had reset it to an even more agressive rear camber (I have decent before and after measurements to compare)!
BMW service tend not to give you input into their KDS process, and I'm not sure as to how diligent they are when they set up the car - WIM are fastidious in achieving accurate settings, whereas the numbers that were measured post KDS where a little out of kilter. Probably not enough to be noticeable, but nevertheless indiciative of the care taken in setting up the car.
It confuses me as to why BMW do this - they don't necessarily benefit from replacing the tyres, and it can't be great in terms of customer satisfaction when your car chews through a set of tyres. Moreover, how many X5 owners drive their cars to the point where those extra few degrees of camber make a difference to the handling?
With the cost of these tyres it's well worth spending the money to get the car set up properly. But beware - not all tyre centres have the equipment or expertise to do this well.
::)