As constructed by LeighSA, about 3 years ago. Biggest drama in Oz is getting the appropriate tyres (hey spellchecker, that is tyres, not tires
Made a mistake with the current one, it's just a passenger car tyre so I don't expect the mileage. But everything else said earlier in the thread holds true. I was quite surprised that the rolling radius is so similar to the standard 17" rear and the 15" tyre doesn't actually change as much during wear due to less tread depth.
I recall wearing out one bike tyre in 1200km. Far too expensive.