I don't know anything about those E3 ones, but it would take a lot of convincing to get me to move away from the NGK Platinum or Iridium.

I replaced the plugs at about 170k in my new-to-me 3.0i, with no records of them having been replaced before, but thinking they could not possibly be original. After replacing them, I was convinced they were the originals. They said BMW on them, along with NGK. They appeared uniformly well worn, although not damaged. Removing them from the head was difficult, as if they had been there for a long time. BUT, they were functioning perfectly well. I noticed no change when replacing them with NGK BKR6EQUP (Platinum), exactly like the ones that came out, except no "BMW" on them.

I don't see much up-side from trying something different from the specified NGK Platinum or Iridium, and there is always a risk with something that has not proven itself.

But good luck if you try them out, and please keep us posted if anything interesting happens.

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2001 X5 3.0i, 203k miles, AT, owned since 2014