Note: For all new readers, there is a follow up from E3 at http://www.wrenchheads.net/2011/01/03/reply-from-e3-about-their-spark-plug-issues/. Basically get in contact with Chris Lacouture @ clacouture@e3sparkplugs.com, they want their problem plugs back and should issue you a refund under warranty.
Have you heard about E3 Spark Plugs? Diamond fire technology for much better spark. The US EPA endorses them, saying these plugs actually make a difference in how the fuel burns, instead of just how long the plug lasts.
I decided to give them a try in my Chrysler New Yorker. Who knows how long the old plugs have been in there, but they have been changed before (Bosch Super Plus came out) and wanted to see what they were all about. They promised a smoother running engine, more fuel mileage, and long life (5 years or 100,000 miles, whichever comes first for warranty).
Hit the jump to find out how they fared with me: