I'm not sure that's really indicative of their longevity. They were only ever a very small part of the market, and the C&V crowd tends to be heavily into steel bikes. For example, even though they were introduced in 1986, they're apparently excluded from l'Eroica. So, there may be plenty of completely usable Kestrel bikes out there, sitting in garages. I have seen one in the flesh, out on the road.