Apparently that word 'enhanced" could be used with ANY of them. Part of the tip is Iridium and part is Platinum and best I can tell(read) they all are made that way. Lots of posts on other car forumns saying same thing about idle,mileage,price and such. Several posting on a Ford forum tell users of these plugs that the better idle can't just be from a plug replacement. That it must be from just installing new,fresh plugs. Others know better.
2009 Quad Cab SLT White,Hemi,2WD,20 inch wheels,3.92 gear.2003 Quad Dually 4x4,6 speed,4.10 gears,diesel.Banks 4 inch exhaust,Afe Pro Guard filter,Rottech crank sensor mod.Amsoil fliuds front to back.08 Corvette Convertible.