Sorry about your gold plated plug experience but iridium plugs are vastly superior . It has to do with the fine wire electrodes , they give improved combustion and they don't foul in 2 strokes .
No spark is going to foul in 2 strokes if the rest of the engine is OK.
If you have worn piston rings, piston, if you have wrong mixture and try to fix that with spark plugs, that brings a whole different set of problems.
Fancy spark plugs are a gimmick, a fad, but that kind of fad has its own audience. I always say that if spending a few bucks more will ensure one's peace of mind, it's worth it. It is all about psychology - people feel better if they pay more, because they think they have a "premium good" with them just because the price is higher.
The spark plug story is just as old as synthetic vs. mineral oil discussion. People have started exaggerating so much with Internet and stuff that they change oil every 500 or 1000 kms, while 3-5000 kms change intervals for scoots with modern oils are just as good. Also, people use expensive synthetic oils in small scoots, while air cooled motorcycle engines that spin to 12.000 rpms and develop 150+ hp /1300 cc do just good using semi-synthetic oils that is changed every 8.000 kms.
Once again, people are free to decide for themselves, but that does not change hard facts.
The only thing I can promise is that fancy spark plug / synthetic oil thread will resurface next week on this and every other scooter/car forum again, again there will be someone realistic like me, and someone who swears in unparalelled quality of fancy plugs and esther-nanotech-synt oils...