We currently use the KBGT 741, which is the large insulated steel carafe model. Prior to that, we had the smaller thermal carafe model. They're very good machines.
The only Chemex I'm familiar with is the classic pour-over, so it's kind of an apples to oranges comparison. It's no accident that the Chemex has been around as long as it has, and it has no shortage of fans. I just prefer to flick a switch and wander away for a couple minutes, then come back to a full pot of coffee.