The Vigilant series I is nearing 40 years in existence. That might give some time-line benchmark to the age of those of us with the knowledge shared on this forum. I don't count myself in that group as I was burning wood back then in an old Defiant (series I)
I'm betting that these work-horse cast iron stoves will be around as long as the century old cast iron base burners. Most of the operating experience will be here, maybe forever?