Coming from a Japanese vehicle background, I never trust anything but NGK or Denso. Our first German car was a 1.8 turbo Beetle, and that came from the factory with NGKs. That being said, I put in NGK BKUR6ET-10 @ $5/each in my 230k. But I change my plugs more frequently as a habit, especially since it's so easy on our DOHC inline-4's. If you have the $ and want the best, go with some iridiums from Denso, NGK, or Bosch. I get all my plugs locally from Advance Auto Parts, they have been the cheapest when it comes to plugs.
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