I don't know if its really worth going this route. Maybe iridium plugs will make a difference under hard riding conditions, but I don't know for sure. Perhaps someone else can tell us the benefits of iridium plugs.
DJ, the big benefit of Iridium plugs are: the plugs center electrode can be made with a much, much smaller wire than either platinum, or gold palladium, or the nickel alloys without shortening the plugs useful life. What that does is allow the spark to be more concentrated at that tiny wire Iridium tip so less current is required for the spark to jump the plug gap.. That can be as much as 3,000- 5,000 volts less than with a production plug type. Is this really a big benefit? Possibly or possibly not.. If the original plug ign system is up to the task & produces a good hot spark then no gain will be noted,, if the original ign system/plug is a little weak in the spark department then an Iridium plug might be of some benefit. They do last much longer due to the hardness of the electrode.
One big benefit in my eyes is it allows a slightly larger plug electrode gap for a little better spark at idle & can in some cases improve the off-idle throttle response.
Are they worth the extra money? About all you can do is try them & see if you notice a difference in low speed throttle response. Again though, they do last a lot longer than conventional plugs.