I took my original BMW ones off at 65K. I like to change that kind of stuff right away when I buy a new 'used' car. The plugs were in excellent shape. I used NGK to replace. cost me less than $45 and was the easiest DIY I have done, I6. I purchased before I found bmwmercedesparts.com They list BMW plugs for $13.79 each. Still pretty high considering I bough all 12 original Mercedes plugs for just under $70. Same 100k life plugs. I wonder what the diff is?:dunno:

The anti-sieze is not for the plugs going in it is for the next time they are changed coming out.[/QUOTE]

seeing how hard it was to get some of the coils out,i regret not getting the anti-sieze.hopefuly it will be easier the second time around(assuming the X can last that long)

Read the whole thread (and other threads on the same topic on here). You don't want to be putting anti-seize or any lubricant on the plugs before installing them. That is from BMW, other vehicle manufacturers, NGK, and Bosch.