I rounded too aggressively. His first iMac was the G4 on a stalk (2002). The second was one of the aluminum pre-Retina Intel models, perhaps 2012. He just purchased his third earlier this year. So, three iMacs in 22 years, but I expect him to keep this one for at least a decade too, at least 5 years, so that will get him to three iMacs in 27 years at minimum.

Whether you say 26 years or 30 years is really not the main point here, that's just splitting hairs.