E3 spark plug inconsistency

That's where they are headed too. I swear I have one where the porcelain around the electrode is cracked.

My experience was really not comparable but I'll tell you about it anyway. I had an 08 Jeep Wrangler for a time. I tried them in it on a whim. Had I not known any better, I would have SWORN it had toque converter shudder. But I took the plugs out and put the stock Champions back in and it never did it again. I've heard similar stories with computer controlled vehicles too.