The economiser is 2k and the kozy king is 3k, like you said. My local dealer told me "the Economiser and the kozy king are basically the same unit, but the kozy king comes with all the bells and whistles." I'm not sure what he means by this, as they look like completely different units. DS Machine told me that the kozy king has a blower that supplies air to the fire, while the heat circulating blower is on. When the blower is off, the draft fan turns off and your stove is basically in idle. Sounds great to me.
I love my basement #4, but the Kozy King is definately a much larger and nicer looking unit. If I like my parents unit, I think I'll upgrade.
If you haven't already, you could call DS Machine. They will tell you where the closest dealer is. They can also give you a price for the unit delivered to your door.