Does Threshold equal newer amp designs?

I remember in the 80's when Threshold had, to my ears, a more full-bodied, richer sound than other SS amps. Some called it a solid-state tube sound. Yet others thought they were analytical and sterile. There are those who think they sound as good or better than even the respected newer stuff out now. Why is Threshold still a popular item in the used market, if later designs are better? I'd like the opinions of former & current Threshold owners, and why you switched or didn't.