I have been a network engineer since the mid-nineties. The company I am in now has19 buildings and 50 plus switches, all Extreme. We use lots of gen one and gen twos — either the X460s or X690s — using the SummitStack. That is our standard variant of the Extreme Networks.
We do have a couple of old 460s and a couple of old 480s, but we use the SummitStack for those versions instead of the Black Diamond.