I ordered one of these the other day from Ebay. Other than shot seals, my C30 Coffeemasters are in mint condition. We can't wait for it to arrive!
I love that rumble, shake and boil sound. It sounds like a volcano! We start the pot, go back to bed for a few minutes and when we hear the sounds the Coffeemaster makes we know coffee is ready. We can even hear the "SNAP!" noise the switch makes when it moves from Hi to Lo.
Back in the day when these were new, I imagine that the consumer didn't have the quality of coffee we do today. I imagine if they did we'd still be seeing more vacuum pots out there today.