I know the XM is not the same as other other M motors in that it does not use 10/60 oil. The S54 initially did not use 10/60 oil either, they changed the oil after a bunch of engines blew up in 2001. I also know it is not recommended in the manual. The issue is you want to be a potato and just follow whatever is recommended or use some common sense once in while. I owned every M3 before this X5 and always changed oil more frequently than say 15K and never regretted it. You seem to be getting your panties in a bunch, no XM owner is upset about anything, chill