I've just gone through this exercise, and what I've found out and been told are the following.

1. All non M E70s have 74.1mm hub diameter all round (front and rears).
2. X5Ms E70s (and X6s) have 74.1mm hub diameter fronts and 72.5mm diameter rears.
3. You can fit X5Ms and X6s wheels onto a standard X5 by simply getting the rear wheels professionally bored out to 74.1mm or fitting a 72.5 hub ring (H&R sell these).
4. Some M Style E70 wheels are available in 74.1 bore size (ie. 333M)

I have the 333M (which came with the X5M) fitted to my 2008 X5 3.0d. I just need to fit the extended guards, as they just fit under. Giving my X5 somewhat of an aftermarket look - which I don't want.

In regards to the 214s, be careful where they were originally fitted on. Some were fitted on X6s. Which means the rears will have a bore size of 72.5. If they came from a non X5M E70, then they should be fine.

I hope that helps.

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H@mmer
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