Its ok champ if your happy to pay 85 bux for 6 plugs and they work for u then thats great.
However iridium plugs have a lower arc over voltage then coppers which results in a colder spark for a given spark gap.
To get around this you run a larger gap for iridiums.
Most manufacturers use platinium/iridium plugs to reduce servicing items, thus making scheduled servicing cheaper. It has nothing to do with power or reliability.
I thought spitfires were pretty much only a replacement for std coils.
The only way to get more juice from your coils is to increase the ign dwell time, thus exposing the weakness of the rb coils and aftermarket equivalents, ther'ye small and heat up quick.
Please refrain from calling people idiots and for the record I run copper plugs with 1.1 mm gaps on a fairly std rb25det and they've done about 15,000 km without any issues, tho i'll replace them soon.