I tried my 60GB 5G iPod in my 20GB 3G's dock. It doesn't fit quite right. There's a bit of strain on the dock connector. It makes electrical contact, but its an awkward fit. The 30GB model might fit, since its thinner than the 60GB. But as it is, I wouldn't feel comfortable using my old 3G's dock with the 60GB vIdeo-Pod.