MOST Iridium plugs have a fine wire Iridium center annode and a regular ground strap.
As of now Autolite's XP series is the only Iridium plug to have an enhanced platinum ground. (Though some OEM GM's might as well as AC Delco uses some Iridium plugs now)
If you were going to spend the extra money and run Iridiums I would only get NipponDenso. They have over & over shown much better results then NGK.
However as a "general recommendation" I would use a Motorcraft fine wire or maybe the new Autolite's XPs.
