1999 Ultra classic
Sounds like we both learn things the hard way. LOLAnother advantage of Iridiums is that they have a much stronger spark in low-voltage situations than traditional plugs. Granted, that's only going to be an issue if your battery is near dead, but it can mean the difference between riding it home or having to get a tow if your charging system fails without you realizing it and you've been out running errands on pure battery power and nearly wiped the battery out.
Ask me how I know. 😛
They also have a tendency to resist fouling better than others.
They're expensive compared to traditional copper plugs on initial purchase, but they pay for themselves in the long run due to their much longer life. Long-term, they probably cost about the same as traditional plugs.