Definitely not complaining about the life of these spark plugs, but was curious (or a coincident) that the OP and I have about the same miles on the spark plugs when it start misbehaving. Still on the original coils.

I swapped out the original Bosch plugs at about 59K and installed these NGKs. The original plugs actually didn't look too bad - so that's why I had decided to give these NGKs a bit more time. I will give these a few weeks until doing a rescan to see if there's anymore misfire(s)

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2004 X5 3.0i
Born 02/04
Delivered 03/04